The mix up

Peter Benjamin Barnes is the older twin to James Buchanan 'Bucky' Barnes. When he was born the doctors mixed up the paperwork saying he might not make it. Put up for adoption he is adopted by Sarah and Joseph rogers. He becomes big brother to Steven Grant Rogers, brothers and best friends that is until he meets his twin helping Steve away from a fight he didn't back down from.

How will they react to seeing each other for the first time?