Katie Lee Biegel's Most Surprising Part of Mom Life Is So Relatable: 'All the Aches and Pains!'

Katie Lee Biegel wasn't expecting so many aches to come with motherhood.

The It's Not Complicated author, 39, appears on this week's episode of PEOPLE in 10 with host Andrea Boehlke, where she shares her favorite part about being mom to 6-month-old daughter Iris Marion, whom she shares with husband Ryan Biegel. Katie says the most surprising thing about motherhood is "all the aches and pains."

"I didn't know that my body would hurt this much," she says with a laugh. "I always have a back ache. But it's worth it!"

Despite those pains, Katie says, "I just love being a mom." She adds, "I knew that I was gonna enjoy it, but I had no idea that I would this much. My favorite thing is getting her up in the morning, going in there and seeing her little face smiling. That's the very best."

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Lee announced her daughter's arrival on Instagram in September. Sharing a photo snuggled up in bed, she revealed her baby girl's name and birth date in her caption: "Welcome, baby Iris Marion Biegel 💕 9.2.20 💕."

In November, Lee opened up to PEOPLE about spending her first Thanksgiving with her daughter, and how Iris makes for the perfect sous chef to help her in the kitchen.

"I bring her little chair in and put it on the floor, and she sits there and it's almost like we're having a little cooking show together because I talk to her constantly to try to help her vocabulary eventually," she said at the time. "I tell her everything that I'm cooking and how I'm doing it. So it's basically like I'm doing a cooking show every time I'm in the kitchen with her."

"Having a baby right now," she added, "it has been the best time to have a baby because I don't have anything else to do except be with her and make brownies."

RELATED VIDEO: Katie Lee Biegel Reveals Her New Mom Self-Care Routine: 'I Watch TV!'

For International Women's Day earlier this month, the chef shared a selfie with her baby girl on Instagram, writing that her "greatest responsibility as a woman is as a mother."

"I want to raise my daughter to be a strong, independent, kind, respectful person, with the confidence to know she can be anything she desires," she wrote.

Watch PEOPLE in 10 with host Andrea Boehlke every Thursday at 10 a.m. ET/ 7 a.m. PT on People.com or watch on YouTube or the PeopleTV app, available on all your favorite streaming devices.