Peter slammed his door with a screech. He was so angry, he couldn't remember ever being this angry in his life.

It wasn't fair. It just wasn't fair. He was their baby. He was their Petey-Bear, they didn't need another baby here. Babies were loud, and messy, and cried all the time, and they didn't even play right! He still remembered trying to play Avengers with Franklin Richards when Uncle Johnny and Aunt Sue came over for a meeting one time. All he did was throw the figures at Peter's head and chew on the ones he liked. There were even bite marks on Ant-Man's helmet to prove it!

It was stupid. It was all stupid. Daddy was stupid, and Papa was stupid, and all his aunts and uncles were stupid for agreeing with them and not him.

It just wasn't fair.

Peter raced over to his closet and pulled out his Hulk backpack from his first day of school last year. He had an Avengers one now, but he still liked this one better. The Hulk was his favorite Avenger. He took his backpack over to his toy box and started pulling out his army men, Avengers figures, and his Hot Rod cars, putting them all in the biggest pocket. He had just started trying to stuff his Hulk plushy in his bag when he heard someone knock on the door behind him.

"No," he shouted. "Go away!"

"Peter? Can I come in, please? I promise I won't let your dads in."

Uncle Bucky. Peter didn't know Uncle Bucky that well. He had just shown up at their house a couple months ago. He had started off being really quiet and always looked a little sad, especially when he looked at Papa, but he was better now. He smiled a lot, and even helped Peter steal cookies when Papa wasn't looking, so he knew he was nice.

"Okay," he said quietly, going to open the door. He saw Uncle Bucky there, smiling, wearing his usual black shirt and jeans with his hair in a ponytail. "But don't let Papa or Daddy in here."

"I think I can do that," Uncle Bucky said, stepping in and shutting the door. He raised an eyebrow when he saw they mess of toys spewed about on Peter's floor, and Peter trying to shove his Hulk plush into an already stuffed up Hulk backpack. "Going somewhere?"

"I'm runnin' away."

Uncle Bucky was frowning when he sat down next to Peter, taking the backpack out of his hands. "Why are you doing that? If you left your Daddy and Papa would be very sad."

Peter just looked down at his Hulk plush, pulling at the fluff coming out of his neck. Aunt Tasha said she'd fix the rip, but she hadn't gotten back from her work yet.

"Pete?"

"They wouldn't be sad," Peter said quietly, looking anywhere except for Bucky. "They would have the new baby to play with, they won't even notice I'm gone."

Uncle Bucky sighed. "Oh, midget you know that's not true."

"Yes it is!" Peter threw his Hulk plush against the wall, turning to look at Uncle Bucky with tears in his eyes. "They won't need me here anymore! They'll have a new baby to play with and take care of! They'll be so busy with her that they won't even notice I'm gone!"

"How can you think that, Peter," Uncle Bucky said calmly. "You know your Daddy loves you more than anything. And your Papa would do anything for you. Besides, if you left, who would blow stuff up with Bruce in the lab? Who would beat Thor at Mario Kart so he doesn't get a big head? And who am I going to sneak cookies to when your Papa is trying to cook dinner, hm?"

"The new baby can do all that," Peter said. He didn't look so sure of himself though.

"She won't be able to Pete. She'll be too little. She'll be a littler midget than you. And since she can't do all those things, that means no one else will be here to do them if you leave. And that would make everyone sad like you feel now. You don't want any of us to feel like you do right now, do you?"

"No," Peter said, a tear slipping down his little cheek.

"Come here, squirt," Uncle Bucky held his arms open to Peter, and Peter sat his lap between his crossed legs. "When I first came here, I used to be jealous too, did you know that?"

"No!" Peter blinked up at his Uncle, surprise on his face. "Why were you jealous?"

"Because of your Daddy. And a little bit because of you. Ever since I could remember it had always just been me and your Papa, you know?"

"Back before Papa crashed the plane to save New York." Peter nodded knowingly.

"Yeah. And even before your Papa became Captain America it was just me and him. And we did everything together. We went to see movies, we talked to pretty girls-" Peter wrinkled his nose- "not the girls with cooties, but the nice girls, the ones that would go dancing with me and your Papa. We even went to Coney Island every couple months so that we could ride the rides and just hang out. And then I didn't see your Papa for a very long time, and when I came back and saw how happy he was with you and your Dad, I felt like I had been replaced as his best friend. Kinda like you feel now, right buddy?"

"Yeah," Peter looked so sad and pathetic when he said it it took everything within Bucky's power not to smile.

"But you didn't lose your best friend. Papa calls you his bestest friend all the time." Bucky nodded.

"Yeah, I realized that after a while. I realized that your Papa didn't treat me any different, and just because he wasn't spending time with only me didn't mean he wasn't still my friend. And then your Daddy and you became my friends too, right?"

"I can be your bestest friend if you want me to, Uncle Bucky."

Bucky laughed. "I'd like that a lot, buddy. But what I'm trying to say is, just because your dads are going to be spending less time with you doesn't mean that you won't ever see them again. They'll still tuck you in at night and drive you to school. They'll still take care of you when you're sick and they'll still watch How It's Made with you every Friday night. There will just be an extra person around for that too. And just because they say they love her doesn't mean they love you any less than they do right now. Do you understand?"

"Yeah, I think so." Peter looked at the backpack still sitting open beside Bucky. "So I shouldn't run away?"

"No kiddo, I don't think you should. Besides, if you left who would teach the new baby how to trick your Papa into giving you an extra scoop of ice cream on the weekends?"

"I don't do that!" Peter laughed.

"Liar, I've seen you do it!" Bucky tickled his sides a little and waited for him to calm down. "So no, running away, ok?"

"Ok."

"And just give the new baby a chance when she gets here, Pete, ok? You might like her a lot."

"I guess." Bucky smiled.

"How about we go get Clint and sneak some candy before dinner, huh?" Peter jumped up out of Bucky's lap, pulling on his arm to get him to move faster.

"Yeah, come on! I want to get some M&M's before Uncle Bruce eats them all!"

"Peter, come and meet your new sister."

Peter stood shyly behind Bucky's legs, staring at the pink bundle that his Daddy was sitting down holding. He looked up at Bucky nervously. Bucky nodded, and nudged him forward with a quiet, "go."

Peter walked up to his Daddy and looked at the baby he was holding down for him to see.

"Peter, this is Sarah. She's your little baby sister."

"Why is she bald?" Peter blurted.

Tony laughed at him. "All babies are bald when they're itty bitty, Pete. You were bald when we got you too."

"Really?"

"Yeah. You wanna hold her?" Peter nodded.

Steve walked up to Bucky and patted him on the shoulder before pulling him into a hug.

"Thanks, Buck. I don't know what you said to him, but it worked so… thank you."

"No problem," Bucky smiled. "You would've done the same for me."

"Daddy, she's so squishy!"

Everyone laughed.