I found a post about someone saying they had a head canon Where Steve's son was born with all his original health problems, the ones he had before the serum. But because Steve knows his son can't even be like him, he's confronted with all these insecurities that he's not a good enough father.

She loves to watch Steve interact with their son. He's so good with James, a natural, and she doesn't know how he does it. He just knows exactly what James wants exactly when he does, and she's constantly in awe of the connection between the two of them.

She grins as she rounds the corner and finds her two favorite boys lying on the ground together, Steve on his stomach and James on his back. Steve is talking to their 7-month-old son as he kicks his legs and babbles. As soon as he spots his mother, though, he squeals in delight and rolls over. As he begins to slither toward her on his belly, Steve scoops him up and brings him over to her.

"Hi sweetheart," she coos to her son, taking him into her arms. "How's my favorite little boy in the whole world?"

"He's perfect, Natasha," Her husband says, tickling one of James' feet. The boy screams with laughter and jerks his foot away, his toes curling under. He curls into his mother's shoulder and smiles at his father.

"Hey there kiddo," Natasha says softly, entering the dark room. "You ready to get up?" A low whine is the only response she gets. She chuckles to herself as James pulls the covers over his head in an attempt to block her out.

"Come on, sleepyhead. The day is starting without you." She gently peels the covers away from her son's face.

"I don't wannaaaaaaa," the three-year-old moans. "Don't make me, Mommy."

"Don't make you what?" Steve says from the doorway. Immediately James' eyes shoot open and a huge smile spreads across his face.

"Daddy, you'll save me! Tell Mommy to let me sleep!" Steve crosses to the little bed.

"Sorry, champ," he grins at his son, "but you have to get out of bed." With a dramatic groan he lifts the child out of his bed and sets him down on the ground. "Go on, if you're quick enough you might be able to snag a few of Aunt Pepper's waffles."

Natasha frowns as she watches her son walk out of the room. There was something off about the way he was walking, but she couldn't quite put a finger on it. She follows her son down the hallway, watches as he grabs onto furniture to help pull himself along.

"Aunt Pepper, Aunt Pepper!" James shouts. He attempts to run across the dining room. Natasha notices that he is favoring a leg though, and sees him start to fall. James hits the ground with a much louder thump than she was expecting, and she realizes that he hadn't even made an attempt to catch himself.

Those thoughts disappear from her mind the second he starts crying, though. She rushes over to him and scoops him up in her arms.

She bites her nails as she watches James play with his friend. They're running around the common room of the tower and shooting at each other with Nerf guns, but she knows something is wrong. James seems to get tired a long time before his friend does, and after a while it's not so much that he's running than he's waddling along as a fast pace in attempt to keep up.

"What are you thinking about?" She startles, not having heard Steve come up behind her.

"Look at how he's running." He can hear the tone of worry in her voice. In the common room, James and his friend Aiden are pummeling each other with pillows, and Steve can't see anything wrong with his son until he attempts a leap off the couch and crumbles in heap on the carpet, hitting his head on the coffee table as he goes down.

Surprisingly, James doesn't start to scream, as his parents had anticipated. He just laughs and rub his head where he hit it and Aiden laughs with him. However, as he starts to stand back up, his parents both frown. He seems to pull himself into a squatting position, using the coffee table to brace and steady himself, then braces his hands against his legs as he tries to stand the rest of the way. Steve takes a few steps out into the living room as he watches his son struggle to pull his top half up into a standing position.

"Hey champ. You okay?" James shrugs but smiles all the same.

"Hey Dad! Can you make us mac n' cheese?" James pleads, latching onto his fathers arm and his smile growing even bigger.

"Daaaaad!"

"I'm coming," Steve shouts back. He kisses Natasha quickly one more time. "Duty calls." She rolls her eyes and he laughs, but gets out of bed and heads down the hall to his son's room.

James grins as soon as he sees Steve. "You're still coming to Parents' Day, right?" Steve helps his son into a sitting position and rests his back against the wall as he helps him undress.

"I wouldn't miss it for the world, buddy."

"Good," James grins. Steve smiles back at his son, but as he helps James get ready for school it's impossible not to notice how sharp his knees and elbows have become, or how much his collar bones stick out, or how prominent his shoulder bones are. His legs are much too thin and the muscles too weak, so Steve has to help support him as he pulls up his pants or brushes his teeth.

"Do you want the crutches or the chair today?" he asks, but he's pretty sure which one James is going to want. Sure enough, he chooses the crutches, and Steve is just starting to help him into the leg braces when Natasha appears in the doorway.

"Oh, sweetheart," she says, kneeling next to her son, "Are you sure you want to use the crutches? I know how tired they make you."

"But I don't like the chair, Mommy." Natasha tries for a few more minutes to persuade him to use the wheelchair, but James vehemently refuses. Neither of his parents have the heart to force him to use the wheelchair; they know it's only a matter of time before he won't be able to walk at all and will be completely dependent on it.

James walks as quickly as he can, aided by his braces and crutches, to the kitchen where the rest of the Avengers are gathered. Thor swings his nephew up onto his shoulders despite Natasha's protests and James giggles happily as he settles himself. Steve bends to pick up the forgotten crutches from the floor.

"Uncle Tony, look! I'm taller than everyone now!" He waves down to his other uncle, showing off.

"You sure are, kid. How's the weather up there?" Thor seats James at one of the chairs at the table and Pepper brings over a plate of pancakes.

"You guys spoil him too much," Natasha snorts, taking a seat next to her son and helping him cut his food.

"Of course we do," Bruce calls from the hall. "He's our only nephew. It's our job to spoil him." She rolls her eyes but it's impossible not to understand.

James wolfs down his breakfast, waves goodbye to his Uncles and Aunt, and is herded out the door by Steve. He chatters excitedly the entire way to his school, saying how everyone's going to be so jealous. When his teacher asks who wants to go first, James practically jumps out of his chair. Steve laughs internally and helps his son hobble to the front of the classroom.

"This is my Dad, Steve Rogers," James beams at his class. "He works for SHIELD and he goes on missions all the time to stop the bad guys. He gets to fight villains and put them in jail, and my mom helps him sometimes. All my uncles help too, and my Uncle Bruce says that every villain is scared of my dad cause they know he'll come and beat them up. My Uncle Tony said that he wasn't always like this, and that once he was just like me. But then he went to a special doctor who helped him get all better. Someday, I'm wanna be just like him."

Steve does his best to hide the look of shock on his face, prays that he's doing it well enough to fool James. Sure, he'd known that James wanted to grow up to be like him; what little boy didn't want to be like their dads at James' age?

But he had thought that James knew it wasn't possible for him. He'd had no idea Tony had told his son about Dr. Erskine, and he makes a mental note to confront him about it later. And now he has no idea how to bring this up to his son.

Later, James brings him a sheet of paper he's been bent over for at least an hour. Steve sees that it's a drawing of their family, including all of James' uncles. He spots two Captain Americas standing next to each other and James points to the smaller one.

"That's gonna be me!" He announces. "Right Dad?"

After he puts James to Bed, Steve cries over the picture.