For immigrant parents whose American-born children want to try out mainstream traditions, eating a turkey at Thanksgiving or putting up a tree at Christmas may feel like a duty, an attempt at assimilation. My parents bought us Christmas stockings, and we decorated our tree with candy canes, ornaments and garlands. But my father wasn’t going to climb onto the roof and stomp around to make us think that Santa Claus had arrived (something my friend’s father did, which may accoun