On Thursday’s episode of Inside the Actors Studio, Harris channels son Gideon Scott and daughter Harper Grace – and PEOPLE has an exclusive sneak peek at the footage.
“They’re pretty quintessential boy and girl,” answers Harris. “Harper is a girl, girl, girl, girl.”
“She wears mermaid outfits and has falls in her hair and you have to announce her when she comes down the staircase,” he explains before jumping into character as his daughter. “And then when you do, she slowly comes down the stairs acting all, like, ‘Oh, me?’ ”
And Harris, 41, says Gideon is “all boy.”
“He loves trucks and construction and he likes superheroes,” the former How I Met Your Mother star adds before impersonating his son. “When he gets mad he puts his fists together and just shakes.”