A 16-year-old German boy, who has wanted to be a girl since age 2, had a secret sex-change operation last month and may be the world's youngest to do so.

The operation that transformed Tim Petras into Kim Petras was paid for by Germany's government-supported health care system.

The surgery was authorized after psychologists confirmed that Kim Petras was "without doubt a girl in a boy's body."

He had been undergoing hormone therapy since age 12.

Dr. Bernd Meyenburg, who treats patients with identity disorders at the University of Frankfurt Hospital, said, "Very few youth psychiatrists have any experience with transsexual developments. The families wander from one psychiatrist to the next.

"I was always against such operations on children so young but after seeing how happy one of my patients was and how well-adjusted after returning from having the operation abroad while still a teenager — I realized that in some cases it is the right decision. Kim is such a case - she always knew what she wanted."

Petras says "she" is happy with the results of the operation.

"I was asked if I feel like a woman now — but the truth is I have always felt like a woman — I just ended up in the wrong body," she said. "I can enjoy swimming, and bikinis, go in the changing rooms without a problem, everything has changed because of this operation. I just can't wait to put on my favorite bathing suit and go swimming like I've never done before."

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