Samsung Galaxy S5

Hello fellow crazy girlfriends just a quick question cause i dont believe my man. I tried to type his name on his phone in facebook because we were trying to find his old facebook account. We did! But i also found a user name that i googled and im pissed about. Whatever i just want to know if you guys know if a phone can remember a word thats "never" been used on his new phone. He has the same sd card, i dont know if that could make it remember it or not.