Penn Badgley

The former 'Gossip Girl’ star, 37, really leans into the “fun” element of being a stepfather to his wife Domino Kirke’s son Cassius, a role he took on when they got married in 2017.

The 40-year-old actress - who also has son James with Penn - said in 2019: “He’s a really good stepdad. He doesn’t have to be ‘dad’ so he can have more fun with him. It’s really nice. The stepparent thing is definitely uncharted territory for me ’cause I didn’t grow up with one, but … he takes care of him really well.”