Brittany Matthews/Instagram; Inset: Paras Griffin/Getty
Brittany Matthews wishes time could slow down with her baby girl.
On Monday, the new mom, 25, shared a photo to her Instagram Story of her breastfeeding her 4-month-old daughter Sterling Skye, commenting on how fast her first baby is growing up.
In the sweet picture, Sterling rests on her mom's lap while wearing an adorable green camouflage onesie and tan socks. Matthews holds her baby against her chest while sporting a navy activewear set.
"Don't know what I'm gonna do when she doesn't fit perfectly in my lap 😭😭😭😭 Stop growing ster girl 😥," the first-time mom writes.
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Earlier this week, Mahomes, 25, and Matthews celebrated their daughter's first Fourth of July with some fashionable photos of baby Sterling.
Matthews shared pictures of her daughter looking cute and festive in a red and white striped peplum swimsuit with a blue headband, while lying on a red blanket, surrounded by red, white and blue stars.
"Happy 4th of July," the proud mom wrote in the caption.
Baby Sterling served multiple Independence Day looks over the weekend, as Matthews shared another photo to her Instagram Story of the infant in a blue and white striped dress, with a red bow in her hair.
She and fiancé Patrick Mahomes welcomed their first child on Feb. 20. The high school sweethearts previously got engaged in September, when Mahomes popped the question on the same day he received his Super Bowl ring.
RELATED VIDEO: Brittany Matthews Says She's 'Soaking in Every Minute' with Newborn Daughter Sterling
The growing family has since celebrated a number of firsts in Sterling's first few months of life, most recently Mahomes' first Father's Day as a dad. "Happy 1st Fathers Day!!! We love you," Matthews wrote on Instagram with a sweet family photo. Mahomes previously paid tribute to his wife-to-be on her first Mother's Day.
"We will share photos of her when we [feel] the time is right," Matthews wrote on social media back in February. "I know the internet will instantly take the photos of her and share everywhere so just preparing myself for my newborn baby girl to be shared to the world! Right now we are just soaking in every minute with her."