Chris Pratt and Katherine Schwarzenegger are adding to their little family.

Pratt, 42, and Schwarzenegger, 32, are expecting baby number two, according to an exclusive report by People. The two stars share daughter Lyla Maria, 16 months. Pratt also shares son Jack, 9, with ex-wife Anna Faris. The news comes just days after Pratt celebrated his wifey’s birthday on social media.

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“Happy Birthday Honey!” Pratt captioned the adorable Instagram post. “You are such a wonderful wife, mother, stepmother, and life partner. I simply can’t imagine how lost I’d be without you. You’re beautiful, tough as nails, reasonable, deeply thoughtful, extraordinarily smart, you’re a complete boss, eternally driven and you communicate like no other. Thank you for everything.

“Thank you for being so instrumental in my growth over the past few years. We fit so perfectly into each other’s lives that our Union is a daily reminder that God is looking out for us. Navigating the odd circumstances of our world is a task I cannot handle alone. And I’m so grateful I don’t have to. Your commitment to helping others is contagious.”

Pratt concluded the adorable birthday post by celebrating the pivotal role Schwarzenegger plays in their family.

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“I’m just so grateful for the harmony you continually bring to our household. I love you so much honey,” Pratt concluded. “Happy Birthday!”

Pratt and Schwarzenegger have not publicly confirmed the pregnancy at the time of this writing.

ET Canada has reached out for comment.