Ariana grande grown up

Pop Stars Transformed:
Ariana Grande Shows
Skin in Revealing
Costume Following 21st
Birthday—Plus 4 Pop
Stars Who Went WILD

Ariana Grande may just have turned 21 on Thursday, but she's already sporting a new look!

During the first day of the iHeartRadio Ultimate Pool Party in Miami, Ariana took the stage in a purple and white circle patterned outfit that not only showed her stomach, but also her toned legs. The Problem singer topped off her look with knee-high retro white boots.

If she keeps up these looks, she might be heading on the same path as these four pop stars who transformed from girl next door to sexy siren!

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