'Kim Possible' premiered 15 years ago -- and fans are freaking out over a new photo of Christy Carlson Romano

She's not a teen anymore, but she could easily pass for one!

Disney Channel's "Kim Possible" premiered 15 years ago today, starring Christy Carlson Romano as the titular teen superhero. She voiced the kick-butt redheaded cheerleader, but her real-life face was well known to fans since she also starred in "Even Stevens," which hit the air in 2000.

In celebration of the big milestone, Romano, now 33, tweeted a celebratory photo that instantly went viral -- because she hasn't aged a day!

"Feeling nostalgic..." she wrote alongside the picture, which shows her flashing a 1 and 5 with her hands.

Impressed by Romano's age-defying genes, many fans urged her to take advantage of her forever-teenage face by heading back to Disney Channel: "Sis, you haven't aged a day so we can pretend it's 15 years ago and you can give us another season," one wrote. The tweet has since been retweeted more than 15,000 times

If Romano does ever make a return to Disney Channel, it likely won't be anytime too soon: The star gave birth to her first child, a daughter, in December 2016. She often shares photos of her little bundle of joy on her Instagram.

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