Jackson and Patrick Mahomes.Photo: Patrick Mahomes/Instagram

Patrick Mahomes

Patrick Mahomes' younger brother is growing up!

The Kansas City Chiefs quarterback, 25, shared a sweet post on Saturday to celebrate his brother Jackson’s 21st birthday. “Lil bro ain’t so little no more! Happy 21st @jacksonmahomes,” hewrotealongside a photo of the pair together, adding the hashtag “much love.”

Jackson also got a special shout-out from the NFL player’s fiancée Brittany Matthews.

“Happy Birthday to my BESTIEEEE! You are the best Brother, Son, Manager, Bestfriend and an even better Uncle to Sterling, Steel & Silver!” shewrotein her own tribute, referencing daughterSterling Skyeas well as the couple’s two dogs.

“We love you so much, and are so incredibly thankful for you!! Cheers to freaking 21!!!!!!🥂🎉❤️,” Matthews added.

The 25-year-old fitness trainer went on to share a fun throwback image of herself with the Mahomes family. In a message to the birthday boy she jokingly wrote, “@jacksonmahomes glad your swag has improved.”

Brittany Matthews and Patrick Mahomes with his family.Brittany Matthews/Instagram

Brittany Matthews and Patrick Mahomes

Matthews and the NFL star recently celebrated another important moment in their life: herfirst Mother’s Daysince welcoming their daughter in February.

The quarterback also shared a tribute to Matthews,writingon Instagram, “Happy 1st Mother’s Day!”

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Brittany Matthews and Patrick Mahones with daughter Sterling Skye.Brittany Matthews/instagram

Patrick Mahomes and Brittany Matthews

“Chillin with the owner ⚽️,” Mahomes captioned onecute family photo.

“Get you a fiancé who rocks your name like you rock his 💯💕💕 @patrickmahomes,” Matthews wrote alongside another post, which showed the football player wearing a jersey with name on it.

source: people.com