She gave birth sometime last week to a girl, Pratt revealed Monday in a sweet Instagram post.
“We are beyond thrilled to announce the birth of our daughter, Lyla Maria Schwarzenegger Pratt,” he captioned a photo of the couple’s hands holding the newborn.
“We couldn’t be happier. Both mom and baby are doing great. We are extremely blessed. Love Katherine and Chris.”
Pratt followed the announcement with a selection of Bible verses celebrating the baby’s arrival.
A day before the official announcement, Schwarzenegger’s younger brother Patrick let slip that his sister had indeed become a mom.
In a video obtained by Entertainment Tonight, Patrick Schwarzenegger said that the couple were “doing great,” giving a thumbs-up to the camera when he was congratulated on becoming an uncle.
“Just got her a little gift,” he said, then flashed a small package with a pink ribbon.
An unnamed source told People at the time that Schwarzenegger had left the hospital and the family was “doing well” at home.
“They knew they were having a girl and were thrilled about it. Kat had a good pregnancy and she is hoping for a quick recovery. So far, so good,” the source said.
“She is going through all the first-time mom emotions. She is extremely happy, but a bit tired and overwhelmed. Chris keeps being amazing though. It’s comforting for Kat that he is already a dad and understands how it is to have a newborn.”
Schwarzenegger, the eldest child of Arnold Schwarzenegger and Maria Shriver, and Pratt married last year in California. They announced Schwarzenegger’s pregnancy in April.
The Marvel star also shares a 7-year-old son, Jack, with his ex-wife, Anna Faris.
Just days ago, Pratt said Schwarzenegger was “ready to pop” while out on a hike together. He shared an...