Pasutto echoed Harris' sweet sentiments, adorably captioned, "Hi my name is Leo. 05.08.16 #thankyouJill #youroneamazingwoman."
The former pro snowboarder also shared a photo from inside the hospital, writing, "Twas the night before a big day and all was calm, till we yelled, celebrated and shook the entire maternity ward down when someone special came into this world."
And it looks like Leo already has an outfit approved by dad!
Pasutto announced "the love of his life" was pregnant back in March with a gorgeous black-and-white shot of Harris showing off her baby bump while posing next to their dog, Nacho.
"Words can't express how lucky and blessed we feel to introduce a new life into ours and that our wish has finally come true," Pasutto gushed. "@nachocilantro on the other hand, isn't quite sure what that means for him but he's excited too."