Title: All I Know
Rating: PG-13
Word Count: ~2,700
Characters: Steve/Natasha, Tony/Pepper, Thor/Sif
Prompts: "Steve/Natasha relationship outsider funny view (Tony) with loving Thor"
Summary: You'd think that after moving in together and having a kid and everything, he'd be totally used to it by now, right? Not the case, apparently.

For: heyailin

All I Know

It trips him out, honestly, Natasha and Steve being happy together.

Not because he's an ass and doesn't want them to be happy, because, hello, they're two of his closest friends. And if he's learned anything over the last few years, it's that with no family of your own you need all the friends you can get, alright? Maybe Pepper gave him that expression, but whatever. It's a pretty good one, and obviously it means being happy when your friends finally suck it up and stop pretending like they aren't already half in love with each other and have been for a while now, even if it's still a little weird to consider it.

He's glad that they got their stuff sorted out. It just took some getting used to, but you'd think that after moving in together and having a kid and everything, he'd be totally used to it by now, right?

Not the case, apparently.

Not even as they're sitting in the living room of his and Pepper's penthouse, talking wedding details with Pepper and Sif.

Shit, they're getting married. What do you even buy them as a wedding gift? Should he order a set of china? Actually, he shouldn't have to worry about a present at all since he's providing his private island for them to get married on, but of course Pepper thinks he should still get them a little something extra.

One of these days he'll learn to say no to that woman. (Except, you know, he won't. But it's nice to imagine.)

Steve's playing with the ring on Natasha's finger, pushing it around with his thumb while Pepper's saying something, but it's not like he's not paying attention. He is. It's as if he just needs to fiddle with the thing. Tony isn't surprised in the slightest. Even before he put the ring on her, Steve's had this sort of nervous tick. Tony's not even sure if that's what you should call it, but whatever. He doesn't need to be near Natasha all the time, but he's noticeably happier just standing next to her, even if she's too wrapped up in the show she's watching or the book she's reading to pay much attention to him. And when he's near her, he just has this inherent need to fuss – playing with her hair or massaging her shoulders and all that. Even before they'd become "official", he would bump his shoulder into hers, nudge her with his knee, give her a comforting squeeze. And she welcomed every touch.

He couldn't – and still can't – keep his hands off of her.

Tony's pretty sure the phrase sickeningly cute was created for people like them.

"You seem troubled, Stark."

Thor looks at him, eyebrows raised. Tony shrugs and lifts his glass to his lips. "I'm not troubled—just observing," he corrects.

"Do you often observe with such troubled expressions?"

Tony rolls his eyes as Thor chuckles deeply, amused by his own wit, and Tony takes a sip of his drink instead of replying, because it's kind of hilarious when Thor thinks he's funnier than he actually is and Tony doesn't want to ruin his moment. (See? He can be a nice guy if he wants to.)

And, alright, he kind of misses the guy. His and Sif's trips to Earth have been less and less frequent, which is understandable and everything, considering they have, you know, nine realms to protect, plus their two kids and one more on the way. Tony's got money on it being a girl. Sif's had nothing but sweets ever since they came and you know what they say about that. He's a man of science, obviously, but he might've Googled a few superstitions when Pepper first got pregnant and he's guessed every baby gender right ever since, so.

Anyway.

Pepper and Sif drift into another topic of conversation as Steve leans in and whispers something into Natasha's ear that has her laughing. Yeah, that also took some getting used to after those two went "official" – Natasha laughing. Tony's heard her snicker before, chuckle a few times, but it wasn't until Steve that he heard her laugh and giggle. Natasha freaking Romanoff giggled and it actually sounded pretty cute, too. She has this soft, genuine tone to her voice, and she crinkles her eyes and tips her head back and sort of shakes her head.

She looks so relaxed when Steve makes her laugh, so completely happy. It's… really great, actually.

Definitely makes it easier to forget for a moment that she knows fourteen different ways to kill a man with her bare hands.

"They're good for each other," Thor comments, gesturing to Steve and Natasha. Tony shrugs one shoulder. "You do not approve of them?"

"What?" He throws Thor a look. "Of course I do. Not that me not approving would stop them from being together, anyway. Actually, they'd probably just rub it in my face even more just to get to me if it did. So it's a good thing that it doesn't."

Thor arches an eyebrow at him again. "You have a way with words, Stark."

"That's not very insulting considering it's coming from Alien Shakespeare, so," Tony mumbles.

Thor chuckles and claps a hand against his shoulder. (Ouch.) "I'll admit, even after all these years, I do not know Natasha as well as I probably should," Thor starts, turning to look at Natasha again as she graces Steve with a smirk as the guy tucks her hair behind her ear. "But it's easy for anyone with eyes to see that this is the happiest she's ever been."

"Yeah," Tony agrees, because he's not too big of an ass to admit that. It is obvious to anyone with eyes that this quasi-domestic life Natasha's found for herself suits her pretty well.

Just like it's obvious to all of them that Natasha's made all the difference for Steve, too. Tony only heard, vaguely, about what Steve was like when they first thawed him – distant, closed off, pretty much a shut-in. Tony can't really blame the guy, to be honest. It must've been a hell of an adjustment to wake up from "death" as if it'd happened just a few days ago when, in actuality, you're in a completely different decade. New York helped with that a little bit more, in that he actually bothered to be part of this new timeline he got thrown into. But Tony and Steve hung out a few times after New York and before Washington D.C. and there was still something off about him. And Tony could tell this because he'd been in that same place not too long ago, where you're kind of just getting through the days, not really living them. Steve tried to appear as if things were better, but it was all over his face.

And then after Washington D.C. – god, that was just a nightmare.

Tony has no idea how a guy could seem livelier and even more restless at the same time, but he did. Tony had assumed it was about Hydra, and then Bucky, when he found out about that part later on. And yeah, those two things definitely hovered over him for a while.

But the constant checking up on Natasha made it apparent what – or who – really occupied the guy's thoughts. The guy came this close to getting a good blast in the head.

(What? The Iron Man suit has a low enough setting and Steve's a durable guy, anyway. He would've brushed it off just fine.)

Tony still hasn't gotten the full story on exactly what happened between them during and after Washington D.C. and, alright, that irked him for the longest time. But after a few near incidents of indecency, Tony's sure that the lack of details is probably for the best. And he doesn't know whether to be weirded out or to pat Steve on the back for everything.

Tony doesn't realize he's made a face until Thor lets out a booming laugh. He does that sometimes (all the time) because he's so easily amused, so it doesn't even startle anyone.

"I know that face," Thor says, shaking Tony's shoulder a little. "You've caught them in the act before."

"God, no – absolutely not," Tony blurts out. "It's come pretty damn close a few times and that's as far as it'll ever get. I can't even look at them for a few minutes after."

"You have two kids of your own, Tony. There's no need to feel inappropriate."

Thor's still laughing and Tony looks at him like he's crazy. He is crazy. "Yeah, I know all about the birds and the bees and they have a kid already and all that jazz, but that doesn't mean I want to walk in on it happening!"

"What birds and bees?" Thor mumbles under his breath, looking amused. Tony just shakes his head. "Well, perhaps you and Pepper are much more controlled than the rest of us," Thor says, smiling at Sif. Tony makes another face. He can only imagine what memories might be going through the guy's head with that smile. "You'll find that the palace of Asgard has little privacy when you're always being sought out. It seemed like a miracle that Sif conceived in the first place, let alone twice more, but we made the most of our quality time."

Okay, this conversation needs to end like, now.

Luckily, this is when Nikki, Modi, and Miles come running down the hallway from Nikki's playroom. "Baby James is awake," Nikki announces.

Pepper presses her lips together, fighting off a grin. "That isn't because you woke him up, is it?" she asks.

"No," Modi replies smoothly. Tony and Thor exchange knowing looks. (That means yes.)

Sif raises her eyebrows and Modi's smile turns apologetic, even a little bit sheepish. He's such a good kid. Maybe a little overly excitable sometimes, but it's clear that he adores his parents and genuinely feels bad when he's misbehaved even a little. Miles, on the other hand, just flashes them that charming smile of his that Pepper says is all Tony, which, yeah, no room for argument there. That kid can weasel his way out of anything, and now that he's the one on the receiving end, Tony realizes this isn't always a good thing, but whatever.

"Thrud is still asleep?" Steve asks.

"Oh, I don't doubt it," Sif says with a laugh. "That girl is her father's daughter, after all, and her father sleeps like a rock."

Thor chuckles and takes another sip of his drink. Sif glances over at him and winks.

"Sorry for waking Baby James," Nikki tells Natasha.

"It's alright," Natasha replies with a bit of a laugh, standing. They can hear James's soft cries coming from the guest bedroom where Steve had set him down once he'd fallen asleep. They probably didn't hear it before because the kids were being so loud. "He just doesn't want to be left out of all the fun," she adds with a wink.

Steve watches as Natasha goes to pick James up, with that stupid smile on his face that he always, always gets when it comes to Natasha and their son.

"Why don't you guys take a snack break?" Pepper suggests to the kids in that tone of voice where you know it's not really a suggestion at all.

(True story: the first time Pepper ever used that tone with him, Tony knew, without a doubt, that she'd be great mom someday, if that's what she wanted to be. And he was right.)

"I'll help," Steve offers.

And, because (of course) Nikki absolutely adores her Uncle Steve, she squeals in excitement and jumps into his arms as he gets up, clinging onto him tightly. Steve chuckles and squeezes the girl a little in a hug, and Pepper stands, too, lifting Miles into her arms and holding him at her hip. Modi leans over and presses a kiss Sif's cheek before following Steve and Pepper into the kitchen. He's been doing that a lot lately, Thor told them – ever since he'd found out that his mother was pregnant again. Tony will admit that that's pretty cute.

Thor walks over to his wife and Tony doesn't really feel like standing all alone, so he follows.

"Feeling alright?" Thor asks, sitting beside Sif on the couch and flattening his palm over her belly. Tony can't help but grin a little at this, remembering the first time he felt Nikki and Miles kick beneath his palm when he'd had his hand over Pepper like that.

"I'm fine," Sif reassures, placing her hand over Thor's. "You should enjoy my pleasant mood while this little one is still content to stay put."

"You are always pleasant for me," Thor replies.

"Good answer," Sif laughs. "What were you two so amused by, anyway?"

"We were just talking about the happy couple," Tony answers, gesturing with the hand holding his mostly empty glass to the spot Steve and Natasha had occupied on the couch.

Sif makes a noise of understanding as she gets this smile on her face. "They are very excited for their wedding day," she points out. "It's quite charming."

"Oh, I seem to remember another bride who was quite eager to be married," Thor comments with a bit of a smirk.

"You were no better," Sif reminds, pushing at his shoulder half-heartedly. Thor chuckles and shifts closer, pressing a kiss to her temple as she smiles up at Tony. "And Pepper has shared a few stories with us about you as your wedding day approached, so you are no exception, either," she tells him, and Tony lifts his hands up in a gesture of surrender.

"Hey, I never said it wasn't charming," Tony insists. "They get to start this next chapter of their lives together and it's all very exciting and romantic."

"It is," Sif agrees easily, smile turning serene.

Tony wonders, for some reason, if she's thinking a little bit about herself and Thor, too. She's mentioned it before, how she understood what Natasha was going through emotionally when she'd been hesitant about even admitting that she had those feelings for Steve in the beginning. Sif hadn't been around to witness any of that but she'd heard the stories. Tony remembers Sif saying that it's hard to open yourself up like that when you thought that kind of future was taken from you. He knew she was talking about Thor and Jane, and, yeah, that was different from what Natasha had gone through, but the feelings were the same – the scary feeling that, as soon as you got comfortable, someone was going to take it away.

So, yeah, as annoying as it was sometimes, watching Steve and Natasha dance around each other, he tried his hardest not to step in. There was never any real doubt that those two would come together eventually, but they needed to do it on their own or it wouldn't have worked.

And now things are great. And he is happy for them, despite everything he might say or do suggesting the contrary, but he's never been great with sentiment, so whatever.

His attention is redirected when he hears Natasha coming down the hallway with James in her arms, murmuring something as the little guy glances around slowly, still half-asleep. Steve wipes his hands on a kitchen towel and sets it aside, walks over and sets his hand over the small of Natasha's back as he pulls them close. James is the kind of kid that looks like whatever parent he happens to be with, so when you get all three of them together, you're not quite sure who he looks like more. He's kind of a perfect blend of them both.

They're cute, this little family. And they're really good at being a family. Tony would like to say that it's a surprise, but really, it's not.

James squirms a little, winding his chubby arms around his mother's neck and plopping his cheek against her shoulder. Steve tucks them into his arms, presses a kiss to Natasha's cheek and then says something to her that makes her smile brightly.

"Sickeningly cute," Tony says to no one in particular. There really is no better phrase for them.