Woody Allen had been having a relationship with Mia Farrow, and they had a child together (although they never technically married and he never adopted Mia's other children as his own). Then it came out that he'd also been having an affair with Mia's adopted daughter, who was 22, making that a 34 year difference between Woody and Soon-Yi. Five years later, Woody and Soon-Yi married, which just brought in all kinds of drama, because Woody had been playing father to Mia's kids, so now Soon-Yi's brother was now her son as well. And while Soon-Yi has said that she never viewed Woody as her father, it was still technically a stepfather/stepchild relationship.

It's just creepy.