DAD / JAMES.
It hasn't been all along, James. I've only been here, in this world, since 2009. Before that I lived in a version of the timeline we were in before. No alternate universes like this, no unexpected future kids or dozens of versions of one person. I'm becoming the expert on having so many different memories and unexpected years on me, it's hard sometimes to know the difference between them. I have memories from where I was originally born. Losing Buck, joining the Avengers, fighting Ultron, the Civil War, which I'd rather not discuss. It was a desperately lonely life I had there, filled with very little happiness, just resignation. I have memories of a portal that took me to Hawaii where I was for many years, where I eventually chose to retire and hand the shield to someone else, and then I was taken from that place and brought here. And now I have a second set of memories from another version of that world, where Bucky actually married me before a decade or so past, and we all lived in Brooklyn together as a family.
They're all smushed together, and I can't change that. Adapting is the only thing I think I've really been good at, since there isn't really another choice. I'm glad I remember everything, even if it's caused one hell of a headache.
And I wasn't a father until the day I met a red haired teenager who fell out of a portal and let me be. I experienced that joy twice. Loving him doesn't make me love you less or differently, kid. Just like loving me didn't make you love your parents or Tony or the Peppers any less or differently. We're a family. Our family's bigger now, but it doesn't have to swallow you whole.