Patrick Mahomes has a mini-me on the way!
The excited family is seen enjoying the occasion in pictures exclusively optioned by PEOPLE.
After squirting blue liquid from toy guns, the parents-to-be cheered alongside their guests before Mahomes jogged away and jumped, clothes still on, in the pool.
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Mahomes and Matthews, 26, announced that they are expecting their second child in joint Instagram posts late last month.
"Round 2!" they simply captioned their trio of pictures, which featured the couple with their daughter and an ultrasound image.
Paras Griffin/Getty Patrick Mahomes and Brittany Matthews
"Big sister duties ... coming soon," read Sterling's sign announcing her sibling-to-be in the shots.
The longtime couple's baby news came just two months after they married in Hawaii following their initial engagement in September 2020. They met while attending Whitehouse High School in Whitehouse, Texas.
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Last weekend, the fitness trainer honored her NFL star husband on Father's Day by taking him and Sterling on a boat outing.
Sharing a heartwarming picture of Mahomes with their daughter on his lap, Matthews wrote on her Instagram Story, "It's a boat day for Father's Day!"
"Love these 2 to the moon ❤️," she added.
She also posted a carousel of images featuring Mahomes, Sterling and herself in a tribute on her Instagram grid. "Happy Father's Day to this incredible Dada! We love you so much! ❤️," Matthews captioned the post.