Tony Stark wasn't reborn in that cold cave in Afghanistan, nor was he when he built the first Iron Man suit. Tony Stark was reborn the moment he discovered fatherhood in the form of young Peter Parker.
Similarly: Steve Rogers wasn't reborn in Brooklyn when Dr. Erskine dimmed the entire state and sent super serum searing through his body, nor was he when he attempted a suicide mission to Azzano, chasing the heels of his lover Sgt. Barnes. Steve Rogers was reborn the moment he discovered fatherhood in the form of beaten and broken Michelle Jones who wasn't afraid to tell you where to get off.
An MCU AU in which the Avengers are fam; Peter is Tony's biological son; the US has spent entirely too much time and money denying the great love affair of Captain America and Sgt. James 'Bucky' Barnes to give up now; MJ finds herself the adoptive daughter to a traumatized war hero who would rather immortalize his dead lover in sketches than deal with the reality of being forced seventy years out of his own time days after said lover's death; and Clint and Nat are too close to marriage and if the whole squad doesn't show up to their nuptials, they might stab their friends
