I was today years old when I learned that sean astin l i v e d the plot of mamma mia
so for those who are asking it basically went like this:
around the time of his birth sean astin's mother patty duke had three highly publicized affairs with three different men: desi arnaz, jr., michael fell, and john astin
most people at the time believed desi to be sean's father, but patty released that john astin was actually sean's biological father. this seemed to be confirmed when patty and john got married and stayed that way for thirteen years.
when sean began to hear rumors that his actual biological father might not be john, he reached out to both desi and michael and formed close relationships with both of them
later he took a dna test that confirmed that michael fell was his biological father, but he remained close with all three men, citing john (the man who raised him) as his "true father."
Master Frodo, here we go again