Chris Pratt and Katherine Schwarzenegger Reveal Daughter's Name and Share First Photo

Chris Pratt and Katherine Schwarzenegger have officially announced the birth of their daughter.

Chris Pratt and Katherine Schwarzenegger have officially announced the birth of their daughter, whom they've decided to name Lyla. Both 41-year-old Chris and 30-year-old Katherine shared a picture on Instagram of them holding their baby girl's hand on Monday.

"We are beyond thrilled to announce the birth of our daughter, Lyla Maria Schwarzenegger Pratt," Chris wrote, also sharing two Bible verses. "We couldn’t be happier. Both mom and baby are doing great. We are extremely blessed. Love Katherine and Chris."

Meanwhile, Katherine wrote, "We are beyond thrilled to announce the birth of our daughter, Lyla Maria Schwarzenegger Pratt. We couldn’t be happier and we feel extremely blessed! Love, Katherine and Chris."

A source also told ET on Monday, "Katherine and Chris welcomed their first child together, a girl. The couple is so excited for their new addition and have been showered with love from their family and friends. Chris was there for the the birth and the couple can’t stop taking their eyes off their daughter. Katherine and Chris are doing well and Katherine is enjoying the experience of being a first-time mother."

"Giving birth was such a special moment for Katherine," the source added. "She was overcome with emotions when she first held her daughter and was so thankful to have Chris there. Everything is new for Katherine and she’s glad Chris is there to help her through everything."

The couple's first child together joins Chris' 7-year-old son, Jack, whom he shares with his ex-wife, actress Anna Faris. Chris and Katherine got married last June in an intimate ceremony in Montecito, California.

Katherine's brother, Patrick Schwarzenegger, also confirmed the big baby news in an exclusive video obtained by ET on Sunday.

"They're doing great -- just got her a little gift," Patrick said while leaving a market in Santa Barbara, California, with a package with a pink ribbon.

Watch below:

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