Sean Astin is Patty Duke's oldest son. Sean's birth was surrounded by controversy, because no one knew for sure who his father was. Patty was dating Desi Arnaz Jr. when she got pregnant, but was sure that she had not been with him at the time of conception. Patty believed that her affair with John Astin resulted in the conception of Sean. However, also during this critical time period, Patty was married for thirteen days to a man named Michael Tell. As a result, Sean grew up unsure who his father was, only aware that the man he thought was his biological father was forced to adopt him because Patty was not married to him at the time of Sean's birth. Despite all this, Sean grew up to be a stable, confident young man who began his own acting career as a child alongside his mother in an after-school special movie called, Please Don't Hit Me, Mom.