The 31-year-old appeared on The Drew Barrymore Show on Monday where she spoke about Lyla, nine months, calling her "the cutest little angel I've ever seen".
"I'm obsessed with her!" Katherine told host Drew Barrymore. "And it's the most fun role and experience that I've ever had and I love absolutely every minute of it. It's such a joy. She's perfect."
WATCH: What you need to know about Katherine Schwarzenegger in just 60 seconds
Katherine also spoke about how she knew "right away" that husband Chris was 'The One' after being introduced to the actor by her mother, Maria Shriver, at church back in 2018.
"We both knew right away that this is where our relationship was headed and we clicked very quickly and so he's the best," she gushed.
"And I am so, so grateful and it's so beautiful to be able to watch him step into this new role of being a girl dad and he's the best husband and best dad and I feel so grateful every single day for him."
Katherine and Chris will soon celebrate their second wedding anniversary
Katherine and Chris tied the knot on 8 June 2019, after a whirlwind one-year relationship.
Sharing the happy news on Instagram at the time, Chris wrote: "Yesterday was the best day of our lives! We became husband and wife in front of God, our families, and those we love. It was intimate, moving, and emotional.
"We feel so blessed to begin this new chapter of our lives. We are so thankful to our families and our friends who stood with us and grateful to Mr. Giorgio Armani who created a once-in-a-lifetime dress for Katherine to wear and for me, the perfect suit. This morning we feel nothing but blessed."
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