Mark Hamill Wishes His ‘Son’ Sebastian Stan a Happy Birthday

Mark Hamill continued to play into a gag where he pretends to be the father of Avengers: Infinity War star, Sebastian Stan, on Monday when he wished his “son” a happy birthday on Twitter.

The joke is based on fans noting that Stan looks a lot like the Star Wars: The Last Jedi star at a younger age. It really took off when Captain America: Civil War came out back in 2016, with lots of photoshopped memes spreading around the net. At the time, Hamill took it with good nature and posted his own side-by-side shot of the two with the caption, “Sorry to disappoint you but I refuse to say ‘Sebastian Stan-I AM YOUR FATHER!’ (even though, in fact, I am.)”

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Now, for Stan’s 36th birthday, Hamill made sure to wish his “son” a happy birthday, while also making sure to take some good-natured swipes at his two actual sons, Griffin Hamill and Nathan Hamill, noting “”Wishing Sebastian Stan the happiest of birthdays. I’m beginning to believe he might actually BE my son, cuz just like @NathanHamill & @GriffinHamill, he never calls… he never writes… C’mon kids- would it kill ya to drop your old man a line? #Ingrates.”

Wishing Sebastian Stan the happiest of birthdays.