@britney spears / Twitter 1 / 16
@britney spears / Twitter 1 / 16

Brit's boys are getting so big!

And Britney Spears couldn't be any prouder of her sons, Jayden James, 5, and Sean Preston, 6! The newly engaged pop star, 30, showed off some action shots of her tots on Twitter this week.

PHOTOS: More pics of Brit's adorable boys

On Tuesday, she uploaded a picture of Sean Preston, her "little Hercules," flexing his muscles and "enjoying his gymnastics class!"

PHOTOS: Sean Preston and Jayden James's cutest moments

The next day, she tweeted a photo of Jayden James "having some hair raising fun on the trampoline."

PHOTOS: Inside Brit and Jason's romance!

While the boys' biological father is Spears' ex-hubby Kevin Federline, her fiance, Jason Trawick, plays a huge role in Jayden James and Sean Preston's lives. "Jason is just amazing with the boys," the multiplatinum singer raved to Us Weekly. "They look up to him so much. They adore him. He's their hero."

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