Bikini-Clad Jamie Lynn Spears Shares Poolside Pics with Daughter Maddie, 3

Mommy-daughter bikinis!

Jamie Lynn Spears' mini-me is growing up fast, and it looks like she's already adopting her mama's bikini style!

Spears shared some pics of her and her 3-year-old daughter, Maddie, having a splash via her Instagram account Sunday. In one pic, the 21-year-old singer/actress showed off her pearly whites while Maddie looked shyly off camera.

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In another photo, the Zoey 101 alum put on her best duck face while Maddie gave a thin-lipped smile.

PHOTOS: Hollywood's cutest kids!

Britney's younger sis gave birth to Maddie on June 19. 2008. At the time, Spears was dating and engaged to the tot's father, Casey Aldridge, but the two called things off in early 2010.

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This past February, Spears opened up to Glamour on why, at 17-years-old, she wasn’t on birth control.

"Like many young girls, I was really scared to go to the doctor,” she explained to the magazine. "I was on a Nickelodeon show, and it felt especially embarrassing to ask someone to put me on birth control. . .I did feel responsible for the young girls and the mothers who I probably confused and let down. I apologize for that. But I wasn't trying to glamorize teen pregnancy."

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