Author's Note: I haven't touched this one in a while but here I am. I own nothing.

Childlike Behavior: Derek

Derek watched as Lydia snuggled the small child to her. The redhead had arrived not ten minutes ago and had fallen in love with the tiny version of their friend as the tiny brunette babbled about how pretty she was. Derek couldn't help the growl. Scott pulled him aside.

"Derek we need to talk." Derek was loathe to leave Stiles alone but the rest of the pack was there she would be fine, right? Scott pulled him into the other room.

"What's going on with you? You told me you had the witch handled, that she wasn't going to be a problem. Now Stiles is three! Three years old! And not even Deaton knows how to handle it." Derek shook his head.

"It was handled, but she made me an offer and I refused, she took it as an insult, which it wasn't meant as by the way." Scott rolled his eyes.

"I knew I should have sent Stiles." Derek full out growled. Scott raised an eyebrow.

"See there you go again! Ever since the thing with the darach you've been weird when it comes to Stiles. And whatever is going on with you is now putting her in danger." Derek deflated. "The witch said something to you before she disappeared. What was it?" Derek sighed.

"When you can prove you treasure what you've lost the spell will break. That's what she said, god knows what she meant." A dry laugh sounded from the doorway Derek looked up at Lydia.

"You're really just not gonna say it are you?" Scott raised an eyebrow. Lydia sighed looking down at her nails.

"Say what exactly?" Scott asked staring at Derek.

"What he hasn't admitted since you, Stiles and Allison died to find the Nematon." Derek flinched violently. Scott frowned. That whole experience had been disastrous, the three of them were supposed to have spent a few minutes at deaths door but instead they'd spent sixteen hours underwater and woken to find their timetable shrunk to four hours. Scott turned to Derek.

"What is she talking about?" Derek kept his mouth shut for a moment. Then he glanced at Lydia.

"Where's Stiles?" Lydia rolled her eyes.

"She was getting fussy, Allison is putting her down for a nap." Derek didn't relax. Scott's eyes flashed red.

"Derek you need to tell me what's going on. She's my best friend!" Derek felt his wolf rise in rebellion.

"And she's my Mate!" He regretted the words the second they were out of his mouth. Scott blinked at him.

"What does that mean?" Derek rolled his eyes. Sometimes he forgot that Mr. True Alpha didn't actually know what he was doing, mostly because Stiles was so good at picking up the slack. Lydia rolled her eyes.

"Seriously you fail at being a wolf." Derek sighed.

"A Mate is what it sounds like, a soulmate. Your forever, your always, your everything." Derek glanced over Lydia's shoulder towards where Stiles was. Scott stared at him.

"So she's your…?" Derek nodded looking down at his shoes. Scott shook his head. "Then why haven't you done anything about it? It's been a few months since we beat the Darach." Derek never looked up.

"She's too young… she's too… perfect. Far too good for someone like me. And she doesn't even play for my team." He flinched as something slapped him across the face. The smell of acetone and graveyards told him who it was but both werewolves were staring at Lydia like she'd grown a second head. She checked her nails.

"You're a god damn idiot Derek Hale. If you can't see that girl is head over feet for you you're blind, deaf and stupid." Derek stared at her.

"What do you mean?" Lydia rolled her eyes.

"I mean she looks at you like she used to look at me. Stiles is about as straight as a waterslide but that doesn't mean she can't like boys." Derek blinked at her.

"Really?" Lydia nodded.

"I don't know if she's Bi or Pan but the way she stares at you when you don't have a shirt on she's into both." Derek blinked at Lydia a bright spark of hope igniting around his heart. Scott threw up his hands.

"Ok as weird as this conversation has turned, this does nothing to fix our current problem." A sharp scream sounded from the other room and the three of them raced into the room. A bright orange smoke was pouring from the bench in the waiting room. A figure appeared in the smoke, the same witch from earlier that night. She ran a hand through the hair of the sleeping toddler who was wrapped in a blanket from Allison's car. She held up a finger in front of her lips as the pack growled at her. Allison had a pistol in her hand, she wasn't pointing it though, she couldn't be sure that she would hit the witch and not hurt Stiles.

"You're close. Most of the way there. But not quite yet Derek." Derek howled.

"Take your hands off her!" The witch smiled but didn't take her hand away.

"Only when you admit it, out loud in front of her." Derek snarled as the witch picked Stiles up the girl barely stirring.

"Put her down now." The witch grinned.

"Awww Derek, come on. As much fun as her father might have raising his daughter again, I doubt she'll enjoy going through puberty twice. Just say the words, in front of your pack. In front of her, that's all it takes." Derek growled.

"What do you want me to say? That I can't stop thinking about her? That I have been noticing her scent since she and Scott were looking for Scott's inhaler on the preserve? That every time she's around I want to scent mark her until everyone on Earth knows she's mine, wolf or not!?" The pack blinked at him, Lydia was grinning slightly from her spot behind Jackson. But her smile was nothing compared to the smirk on the witch's face.

"That is exactly what I wanted to hear." Orange smoke billowed around her and filled the room.

The werewolves hacked and coughed as the smoke began to dissipate. Lydia had stumbled outside with Allison trying to catch their breath. Derek lunged forwards through his coughing trying to find the bench through the smoke in his lungs. The smoke blew away and he spotted the bench and more importantly the girl on it. Well no not a girl anymore, a woman. He breathed out as the familiar spikey hair moved slightly as she shook her head gathering the blanket around her.

"Derek? Why am I not wearing pants?" Derek looked away from her his ears going red. Erica rushed forwards and bundled Stiles out of the vets office into Lydia's car. Derek leaned his head on the doorframe as the car peeled out of the parking lot. The girls all heading back to Stiles' house to let her dad know she was alright and to find her some pants. Scott spoke from behind him.

"I don't get it, Stiles wasn't even awake for what you said, which by the way really? Since the day you gave me back my inhaler?" Derek shrugged. Deaton seemed to have a theory though.

"She wanted you to admit it to yourself. She wanted to have sex with you yes?" Derek nodded. Scott glanced at him. "When you refused she was insulted?" Another nod. "That's why she attacked." This time all of them nodded.

"When she figured out that Stiles is your Mate how did she react." Scott spoke up for Derek.

"She seemed a bit more calm then when she was throwing fireballs at us. Like something made sense." Derek nodded and cut in.

"Then she figured out I hadn't told Stiles. She seemed upset." Deaton nodded.

"That makes sense. Mates are rare Derek, nearly as rare as True Alphas or the ability to shift into a full wolf. To not tell someone when you know you've found them it's cruel." Boyd and Isaac nodded.

"He's right."

"You've admitted it to us, now you need to tell her." Derek stared down at his feet.

"Maybe I do."