A Croatian girl baffled doctors when she woke up from a coma speaking fluent German, which she didn't previously know, and is now unable to talk in her native tongue.

Two weeks ago, the 13-year-old girl lost consciousness for 24 hours.

She had been studying German at school and watching German TV shows, but her parents insist she was previously unable to communicate properly in that language.

"You never know when recovering from such a trauma how the brain will react," hospital director Dujomir Marasovic told the U.K.’s Telegraph.

Various experts have examined the teenager, who is from the southern Croatian town of Knin, but all have failed to make a diagnosis.

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