Author's Note:

We all know they're not mine, however much I love them.

This came to me after watching a clip from the episode in the title. Mac brings Mattie to the wall and Harm looks at her like he's suspicious of her intentions and then asks what she's doing that night. Her answer, that she has a date with Webb (she calls the man she's meant to be dating by his last name?) seems calculated to hurt him and make him shut her out. This is what could have happened instead.

My first published fanfiction. This is very exciting! Please read and review. Constructive criticism would be much appreciated.


She watched Mattie and Harm with detached longing. Giving him back the girl who made his world turn, who did more to light up his face and steady his ground than anyone else in Harm's life, was a no-brainer.

Mattie was a good influence on Harm and Harm was a good influence on Mattie. That was all it came down to, she told herself (and, she hoped, he'd do the same for her given the chance).

The way Mattie rushed into his arms, clutching tight round his wide chest and burying her face in his coat, made her even more sure this had been the right decision. He stood there and let her hold him, keeping his eyes on Mac's.

The look on his face was one she had seen often: a dose of distrust (he was suspicious of her intentions), unabashed admiration, and a sincere thankyou like only he could deliver. He had the right to be unsure of her, she supposed, but that look still hurt every time she got it. From any other man, it would make her slightly guilty. From Harm… she had the uncomfortable feeling that all her guilt and shame and sadness might appear on her face if she left the half-smile mask slip.

Her eyes glinted and the decision not to cry was a conscious one. She did that odd little movement, a twitch of her chin that said "what could I do? You belong together" and "you're welcome" at the same time. They were back to having long conversations without words.

At that moment, Mattie told him she wouldn't break, and his eyes dropped. Then his arms came around her too, gripping like she might fade away or run back to her father. Looking at his capped head, bowed over the girl he would call daughter, Mac somehow felt like a voyeur and a benevolent aunt at the same time. She smiled rapidly, all the little lines around her face dimpling in a way that made her even more beautiful. Then she pulled her lips in quickly and said in her soothing voice "G'night".

Eyes up again, Harm watched her walk away for a moment before asking where she was going. She hesitated. In truth, she was going home to stare at a wall or the TV in her pyjamas. Webb was off visiting his mother, and Mac knew Porter didn't consider her "good enough" for her son. She could fabricate a date, and leave these two alone. She could say his name, and watch Harm's face fall – encourage him to shut her out for tonight. Or she could force herself in on their first night together (Harm would be more than happy to have her, she knew) and spend more time with the smart, mature teenage girl she liked and the man she…well…loved.

The uncomfortable thought of imposing aside, there was really no contest. So she took a breath, and answered "nowhere exciting."

Harm smiled, "what, no hot date?"

"No-one as good as yours," she responded, looking down at Mattie, cornsilk hair spread across her back and Harm's hands tangled in it. She didn't know if that was meant to be a subtle dig at Webb, but it came out sounding like one. (God, what do you do when you start calling the man you're kind-of-but-not-really-dating by his last name? The last name your more-than-friends-but-less-than-lovers partner uses with scorn whenever he has to refer to him?)

"Come with us?" he almost seemed to be pleading. There was genuine love and interest and engagement in his tone and she allowed it to pull them together.

"Are you sure?" she asked. She knew she would be upset if she broke that rope now – the shiny golden rope they were building which tugged her by the navel in his direction – but she would accept it if she had to. She needed to make sure he was okay with this.

"Yes. As long as that's OK with you, Mattie?" He looked down at the somehow strong and vulnerable girl in his arms.

"Of course," Mattie answered, "I love Mac." She grinned conspiratorially, and her lips formed something which must have been cheeky because Harm crushed her against his chest as if to stop her mouth. Mac thought it might have been "and so do you."

They were going to get ice cream, Mattie explained. It seemed something of a ritual for the two of them because Harm – normally a health nut – only rolled his eyes slightly, and then demurred. Mattie turned to Mac and began an energetic description of the ice cream parlour. It seemed like she knew every flavour off by heart, and Mac decided she liked the girl already.

"Mattie," she said, "I am so very excited for this ice cream parlour. But I have to ask – have you ever been to Jubilee?"

Mattie shook her head, but leant forward with ever-so-slightly sparkly eyes. "Why? Is it good?"

"You have no idea." Mac stuck her tongue out at Harm's disapproving look and watched his face break into a smile before she turned back. "Their chocolate chocolate is my favourite thing in the whole wide world. But I think you'd be more of a…snickers snickerdoodle girl?"

"SNICKERS?" Mattie was beyond excited. She spun towards Harm, long hair in a time-lapse behind her, and demanded to go to Jubilee "next date." Apparently snickers ice cream was Mattie's favourite in the world, and Mac had "officially won her over."

Mac simply bit back the flirty response she could have given to the "date" comment, deciding she didn't want any stilted responses and helplessly meaningful looks from Harm tonight, and gave Harm her biggest "she's your responsibility at bedtime" grin. There were benefits to being the benevolent aunt, she decided, and shifted back to Mattie's comparison of different flavours.

The moment they entered the ice-cream parlour Mattie made a bee-line for something with toffee, nuts, and at least a thousand calories. Mac swallowed a smirk, a little pleased at the accuracy of her pick. She spent a little time browsing in search of the perfect flavour, only choosing when Harm called her bluff. "Mac. Seriously. There's something here called quintuple chocolate. I think I know what you're going for." She had been eyeing it off for some time now, if they were going to be honest.

They sat on the terrace licking icecream (Harm had a fruit sorbet, to which Mac declared he was taking the fun out of ice cream but which he said he preferred, thank you very much) and enjoying the quiet. Occasionally a car revved on the highway or footprints paced their way up the sidewalk, but Mac could also hear the chirruping of crickets and Harm's calm breathing.

They'd all tasted each other's ice creams, of course – Mattie leaning in for a bite of Mac's and coming out with a pleased look and chocolate all over her face like a beard, then shooting Mac a look at the initial tartness of Harm's fruit sorbet, before the sweet aftertaste kicked in.

Harm had tasted Mattie's first, trying to nip her finger where it clutched the cone in a dad-like move that warmed Mac's heart. He'd hesitated, looking at her, before she shoved her own cone in his direction. Then he'd leant in with dart-like quickness, closed his eyes, and taken a mouthful. Mac wondered whether he knew that did strange things to her stomach. The way he withdrew – slowly, with his eyes still closed and a rare look of unmasked bliss on his face – said perhaps he felt it too.

"Harm, I'm going to taste yours first so I don't have to deal with a healthy aftertaste," she teased, leaning in, and wondered if he'd pulled his cone closer to his face in the meantime because his eyes seemed to be inches from hers. She felt his breathing quicken and leant down to taste the sorbet.

Suddenly, the shimmery illusion of him and her came crashing down. They were sitting on a terrace, on Christmas Eve, with Mattie. She was going to enjoy this, but she would not make it more than it was and she would not do anything she was going to regret later. "Eugh", she said, mock-disgusted at the taste, and swapped Harm's cone for Mattie's. He seemed shocked at the speed of her redirection, but recovered quickly and turned his nose up at both of them. "When you feel sick don't come running to me."

"Oh, don't count on it," Mac and Mattie said at the same time, emotion running through their voices. Grinning, Mattie held up a hand for Mac to high-five. God, she liked this girl. She liked this family feeling, this comfort, the way both of them looked at her like she belonged in their golden little bubble of moonlight and sugar and Christmas Eve. And just as she thought that, it started to snow.

The first snowflake, for her, had always been Harm. Not unheard of, but certainly unexpected, it blazed a fabulous trail for everything that would follow. Keen and yet unsure, it spun through the air in a series of misdirections. Its initial goal, to touch the ground, was all it ever knew. And yet, there was so much beauty in the feathering of its points, the surety of its destination, even if it didn't really know how to get there. She watched this year's first snowfall idly, used to being behind a window or a door, somehow incapacitated and unable to reach it. Then, something clicking in the corridors of her brain, she realised there was nothing stopping her throwing out a hand to halt its journey, touching it and watching it melt before it hit the ground.

All in a second she stood up, eyes glinting like a child's, and held out cupped hands. Some of the snow melted on impact, coating her hands in cheery winter cold. Some slipped through her fingers just slightly and she found herself grabbing for it like an uncoordinated comic-book character before she realised it had already disappeared into the ether created by her hands' pink warmth. Her favourite flakes were those that stuck on her hair and the ribbed woollen arms of her jumper. She knew they would melt eventually, but for now, they were hers.

Sensing his warmth behind her, she felt him smile. "Anyone would think you hadn't seen snow, Marine." And yet she watched him inspect the flakes that fell on the arm of his coat, somehow caught up in the moment and her joy. Mattie told him unceremoniously to shut up, because this was magical, and began to spin in circles. Snow fell in her long brown hair, on her clothes, and on the tip of her nose (which was how Mac found out she could touch it with her tongue.) Her scrunchie ended up covered in it and slowly turning white.

Mac snuck up behind Mattie and touched the cold tips of her fingers to her face. Mattie declared it a matter of war, recruited Harm, and both of them began gathering all the snow they could off the grass. Then they shoved it down the back of Mac's neck.

"AAARGHH!" Mac screamed with all the strength she could muster, declared this "double-war" and started gathering her own. They must have played like that for half an hour (after about ten minutes Mattie switched sides and Mac teased Harm she was recruiting her for the Marines) before Harm declared his intentions.

"Mac, Mattie, I think we ought to get home before the roads are too iced-up."

"Seems sensible, flyboy." Mattie grinned at that, perhaps detecting the affection in the gaze that spread between them even when they were being organised adults. There was always something deeper with those two. "I'll see you, then. Permission to hug the commander's ward?"

Mattie stuck her tongue out and went in for the hug. Harm seemed shocked.

"Come home with us, Mac," he said in what could almost be described as his "wheedling" tone. "There's plenty of space, and you shouldn't be all alone on Christmas Eve."

Something could be said for the way that Mac looked at Mattie at that point, clearly asking for her permission. Mattie nodded, and said "of course, Mac. We'd love to have you."

Harm smiled sideways at the silent communication already occurring between the two. Mac was the best of role models for Mattie, and he had enough love and respect for both of them to allow them to find each other. "Let's go then, my two favourite girls."

Mac grinned and leant over to play-punch Harm, grabbing Mattie's hand for a second in the process when she looked downcast. She looked at the younger girl and whispered: "I have Toblerone in the car."

Mattie perked up immediately, and asked if she could drive home with Mac. Harm looked suspicious, but demurred – not without looking at Mac for a moment, the easygoing mask falling from his face as he made her promise to drive safely.

"Harm," she said, drawing closer, knowing this was important. "I would never hurt your world." And then she and Mattie left, trekking over to her car while Harm stepped out slowly in the opposite direction, mulling over the meaning of her comment. There were two ways – two perfectly legitimate ways – to take it. One was that Mac never meant to upset his world in its orbit, that she never meant to do anything to rock the boat of his life. Then there was the other – the one he suspected Mac had meant but (as always, with their relationship) couldn't be sure – the one where Mac was implying that Mattie was his world and so she would never hurt her.

The second upset him, he realised. It upset him not because Mattie wasn't a big part of his life (she was, of course, and he loved her with all he had) but because of Mac's penchant for consistently downplaying her own part in it.

Over the years, Harm had got to the point where he couldn't imagine life without Mac. He probably spent more time at her apartment – talking, eating, going over case files – than he had in all his girlfriends' put together. He relied on her as a confidante, an advisor and a maker of dispassionate plans. She was his first port of call when a problem arose (personal or professional) or a day needed brightening. In a world which had come to forget the power of friendship, she was his deepest, purest, strongest friend. But both of them knew she was so much more than that.

Calling their relationship a friendship wasn't cheap, but it was insufficient, inaccurate - they had gone beyond platonic friendship a long time ago. He wasn't sure what to call them, but he was terribly glad he had her. If she didn't have anywhere to be this Christmas, he decided it was time to show her and Mattie both how much they meant to him.

Mac's phone pinged and both her eyes and Mattie's were drawn towards it. It only took a second to check the screen and realise it was Harm. "Yup, Mattie, you can open it," she said.

Mattie, normally so forward, hesitated for a second. It was as if she was afraid of the trust Mac placed in her by allowing her to check the text, and even while driving Mac could see the two warring sides of her – one that wanted to open herself up to the world and be the kind of girl Mac could trust, and one that said the world would only scar you if you let it close. Mac was pleased to see that it was the cheery, open youngster who finally won out, looking up with a sparkle in her eyes as she told Mac that Harm had gone past Walmart to pick up decorations.

"Odd that he doesn't have any," murmured Mac, more to herself than Mattie.

"I know, right?" Mattie answered, nearly bouncing in her seat. The image brought a memory to the surface – something about marines and Energizer bunnies. Mac's lip curled in a wry smile.

They got home before Harm, and after debating with herself for half a minute (and realising Mattie must think she was mad) Mac decided it would be OK to use her key. Mattie's eyes were drawn to the fridge as soon as she walked in, so Mac set to making one of her grandmother's recipes, just as soon as she'd grabbed the clothes she kept at Harm's to change into (she didn't want to assume, but her uniform didn't look good with sauce all over it.) Watching Mac cook, so at home in Harm's kitchen, made Mattie smile.

The two chatted merrily until Harm came home. Mac could see a barrage of memories hit him as he walked in the door, hefting a bag of decorations in each hand. His eyes moved from Mattie at the table, absent-mindedly flicking through a book on aeroplanes and talking about someone named Becca, to Mac, occasionally turning to make eye contact with their teenager or check she hadn't missed an ingredient, to the pot bubbling on the stove. He looked slightly shell-shocked. (He would realise only later, going through his thoughts that night, that he'd thought of Mattie as "theirs.")

The two girls turned to look at him slowly, gave matching joyful smiles, and then Mac turned back to the spitting pot while Mattie ran to take the decorations. Watching her look at the bags' contents with the sparkling eyes of a four-year-old ("Ooooh, soooo much tinsel!") he felt a strong sense of imminent dread.

There was soon tinsel everywhere, more baubles than he could count on the tree, and mistletoe (had that been a good idea? He wasn't even sure he remembered picking it up) hung in the hallway. Mattie was bubbly with Christmas spirit, Mac was dishing up something Middle-Eastern and incredible, and his world seemed to have turned on his head. The funniest thing was that he liked it. He felt out-of-control and safe at the same time, and he liked it. He slotted that thought away to overanalyse later and started on the food.

When the meal was done, they gave a collective yawn and Mac got up to start on the dishes. "Uh-uh," Harm said, shooing her away with a pat on the bum and a flirty grin, "you cooked, I'll clean. Why don't you two go watch a movie?"

Mattie was halfway to the TV room already and certainly not complaining. She turned around to grab the arm of a protesting Mac and pull her onto the sofa, saying "it's only fair. And it might teach him to get a dishwasher."

Mac grinned and pulled her into a hug on impulse. "I've been saying that for years. I'm not sure it's changing anytime soon." Mattie softened against her almost instantly, arms around her waist and head on her chest. Mac felt a twinge of something deep in her stomach.

"Well, we'll make it change, then won't we?" Mattie said, and Mac leant back to take in the picture of the teenager with her hair sticking up and that shimmer in her eyes. She would not think about the speed with which they had become a "we" in Mattie's mind. Would not.

They sat down on the sofa minutes later, a bowl of microwave popcorn in Mattie's hand and the TV remote in Mac's. After a little deliberation, they settled on a chick-flick that Mac loved, Mattie thought she'd like, and both agreed Harm would probably hate. They weren't in the mood for documentaries tonight, so he'd just have to endure.

When Harm made his appearance 20 minutes later (he might have cleaned the kitchen a little more than the girls would have anticipated) he found Mattie asleep with her head on Mac's shoulder, and Mac close to nodding off against the sofa cushion. He paused in the doorway a moment, secure in the knowledge that Mac was likely not coherent enough to call him on it and that if she did, he could say he was admiring the fairy lights on the tree.

The whole thing just felt so domestic – his two girls, the chick-flick on the TV, the massive bowl of popcorn they'd managed to almost empty in the time it had taken him to clean the kitchen. They fit together like two pieces of a puzzle, and something inside him seemed to complete itself as they sat there – streetlights throwing their white glow through the half-open curtains, and the Christmas tree bathing the room in colour and warmth.

Loath to interrupt the beautiful scene but feeling like Mattie needed to get to sleep (she'd be just as hyper tomorrow if she didn't sleep now, but he'd like to avoid the angry that might come with it) he tucked his arm around Mattie's shoulders and squeezed. Mac's eyes flicked open almost violently, but he could see the comfortable veil settle back over her features when she realised where she was.

Mattie slowly, drowsily woke up, leaning against his chest as she kicked her feet back into the slippers she'd shed and stood. "Time for bed, I think," he said, looking at her and then at Mac, and Mattie nodded. He brought the collapsible single bed he'd brought for the purpose into the TV room, folded it out and put the mattress on top. Inevitably, it crossed his mind that this could only be a temporary arrangement, but he pushed the thought back. He didn't really want to think about more permanent living arrangements for the two of them tonight. As he settled Mattie, Mac drifted into the kitchen, seemingly waiting to say her goodbyes. When he found her there, sitting on a kitchen chair with one leg crossed underneath her and her chin on her hand as she yawned, she looked as tired as he felt.

"I really should be going," she said after a beat, her husky voice sending shivers down Harm's spine even as his brain processed the nature of her comment.

"Mac, it's late and the roads are icy. Stay here tonight?" He really didn't want her driving in these conditions. He told himself that was all it was.

"I really don't want to put you guys out, Harm. You've got Mattie here and the sofa isn't made up…"

Harm bit back the response he wanted to make, that she was one of them and she belonged there as much as him or Mattie – that he knew Mattie thought the same because she'd told him during the snow fight. Instead he said "No, Mac, don't hurt your back on the sofa. Come sleep in the bed with me. My snoring probably isn't as bad as springs digging into your back."

There was a pause in which Harm thought he'd pushed her too far. Then Mac's lip quirked up in a half-smile. "You make it sound so inviting," she said softly, turning his mind back to years before.

He grinned back, feeling as if a lead weight had been lifted off his stomach. "What can I say?" He countered and stepped toward her.

Mac felt some revelation coming, and she wasn't sure she wanted to hear it. "Tread carefully, flyboy" she heard herself say as if underwater.

"This is beautiful, Mac," he said, his voice approaching a whisper. "She's beautiful, we're beautiful, and I felt tonight as if everything was falling together."

"Harm, I think you're getting this confused. She's beautiful. You're beautiful. Me? I don't belong here. I'm no more than a visitor in your lives."

"Mac," he said more harshly than he intended, catching her hands in his. "You can't really believe that you're a visitor in my life. You mean more to me than words can describe – hell, I was thinking earlier that I don't know how I'd live without you. I rely on you for support and advice and dispassionate plans – you're my first port of call whenever anything comes up. You go TAD and all of a sudden I realise I'm a headless chicken. I want you. I need you. Always."

Mac blinked furiously, holding back tears. "Harm, you've got other responsibilities now. This thing, with us – I want you and need you and rely on you all the time too, but it's messy. It's never going to be something you can package up and present to a teenager as a model of a healthy relationship. I'm not sure what you are to me, but it's definitely more than a friend."

Harm came closer, squeezing her shoulders. "I know," he said, his voice raising slightly in pitch but not in volume. "I know, and Mattie knows. She said earlier that I loved you," Mac bit back a slight smile, "and then she said that she wanted you in her life. That you were good for me and good for her, and she thought we'd all be good together."

Tears came pouring from Mac's eyes, and no matter how many she scrubbed away with the back of her hand more somehow appeared to replace them. This girl, this teenager with her perception and maturity and smile like sunrise, said she wanted Mac in life. That she wanted Mac and Harm together in her future. She'd more than given Harm the go-ahead – she'd pushed him on the road to telling her how he felt with complete peace of mind. And she could never stop thanking her for that.

"Do you think that?" she asked.

"Do I think what?" Harm's hands were still on her shoulders, their warmth bleeding through the fabric of her shirt and falling into her soul.

"That I'm good for her and good for you, and…" her voice cracked "…and we'd be good together?"

"God, Sarah," he said, tears glinting at the corner of his eyes, "I've never believed anything more."

She was seconds short of blubbering like a baby, so she thought she'd get the words out now. For once in her life, the right words at the right time. "I love you. I love you so much, flyboy."

"I love you too", he whispered. "I don't know when I started…and I don't think I'll ever stop." He pressed his lips to her forehead, put his arms around her body, and drew her into his chest as she sobbed.

"And Sarah?" he said, his head atop hers. "You're not the only one crying."

That only made her cry harder, and they stood there, rocking each other, for what felt like hours.

"How long have we been standing here?" Harm asked Mac quietly, arms still tight around her like he'd never let go.

"Well," he could feel her grin against his chest before she tipped her head back to make eye contact, "it's Christmas now."

Harm smiled back and touched his lips to hers. "I can't think of a better gift." And then, watching her yawn, he added "and I think it's time for bed."