And then there were two (or four, as it were).
The actress and author is pregnant with the couple’s second child, they revealed with aid from a NoseFrida snot sucker. In the accompanying photo, the American Pie and Orange Is the New Black alum, 38, had the NoseFrida in his nostril, while Mollen mimed sucking on the tube’s other end.
“This is how I told my son babies are made #numbertwo,” Mollen, 37, wrote on Instagram.
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The pair – who starred together on 2016 comedy series I Like You Just the Way I Am – are already parents to son Sid, 3. After welcoming his first child, Biggs told PEOPLE in 2014 that he “changed completely.”
“That change that happens is so tangible. It happens overnight, and it’s the craziest thing,” he shared at the time.
The feeling is the same for Mollen, as the actress and author admitted her priorities completely shifted when her son was born.
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One family activity that the spouses will likely pass on to Sid’s little sibling? Bedtime stories.
“Reading was part of his bedtime routine from the very beginning,” Biggs said in 2015, adding of one of the charities he has supported in the past, “I’m excited to get Sid involved and have some Milk + Bookies parties too.”
“He loves The Very Hungry Caterpillar,” Biggs said of Sid’s favorite story at the time, joking, “And the screenplay for American Pie. That’s pretty much all he reads.”