Celebrity Parents Chris Pratt Celebrates Katherine Schwarzenegger's First Mother's Day Since Welcoming Daughter Lyla "This is your first year as a mom, your third year as a step mom, and 31st year as a hot momma," Chris Pratt wrote in a loving tribute to his wife By Georgia Slater Georgia Slater Twitter Georgia Slater is a writer/reporter on the Parents team at PEOPLE. She began at the brand in 2018 as an editorial intern and later returned as an intern on the Food team. Upon graduating from the University of Maryland in 2019, Georgia worked as an entertainment intern at USA Today before coming back to PEOPLE as a digital news writer. In April 2021, she began her role as a Parents writer/reporter. People Editorial Guidelines Published on May 9, 2021 01:45 PM Share Tweet Pin Email Photo: Michael Buckner/Variety/Shutterstock Katherine Schwarzenegger Pratt is marking her first Mother's Day as a mom! The Gift of Forgiveness author, 31, welcomed daughter Lyla Maria with husband Chris Pratt last August. To celebrate the special day, the actor, 41, shared a loving tribute on social media Sunday. "Happy Mother's Day to my sweet @katherineschwarzenegger This is your first year as a mom, your third year as a step mom, and 31st year as a hot momma," wrote Pratt, who is also a father to son Jack, 9, with ex Anna Faris."Thank you for everything you do for us. We love you!!" he added.Schwarzenegger Pratt also shared a sweet message in honor of mom Maria Shriver. "Happy Mother's Day to the worlds greatest mother and happy first Mother's Day as a grandmama!" she wrote. "You've taught me everything i know about motherhood, about unconditional love, kindness, acceptance and you mother with such joy and ease." "You are the greatest grand mama to Lyla Maria," she added. "She beams with JOY when she sees you, and today she's all yours! I hope to be half the mother you are. I love you deeply. ♥️" Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories. Katherine Schwarzenegger Explains Why She and Chris Pratt Won't Show Daughter Lyla's Face Schwarzenegger Pratt recently opened up about having an amazing partner in Pratt. In the latest episode of her Instagram Live series, "BDA (Before, During & After) Baby," she chatted with her friend and new mom Iskra Lawrence about the difficulties moms have with body image and the idea of snapping back shortly after giving birth. The author explained that Pratt has "always been super supportive" of her body and how a woman's body changes before and after birth. RELATED VIDEO: Katherine Schwarzenegger Says She's 'Obsessed' with Putting Her Daughter's 'Name on Everything' "He'll look at our daughter and be like, 'Can you believe your body is able to feed our baby?' " she said. "Sometimes, I think — especially as women with this pressure to bounce back after baby — you have to keep in mind that when you're breastfeeding, you need to, as my husband says, 'eat to win,' and to feed yourself so you can also properly nourish your baby. Because for a lot of people, what you eat and how you treat your body also hugely impacts your milk supply," she added. Want to get the biggest stories from PEOPLE every weekday? Subscribe to our new podcast, PEOPLE Every Day, to get the essential celebrity, entertainment and human interest news stories Monday through Friday. Back in August, the couple shared the first photo of their newborn baby girl's hand alongside a sweet announcement about her birth shortly after she arrived. "We are beyond thrilled to announce the birth of our daughter Lyla Maria Schwarzenegger Pratt," the caption on both parents' posts read at the time. "We couldn't be happier and we feel extremely blessed! Love, Katherine and Chris."