She may be a princess someday, but Wednesday night she was a roller-skating flop.

Prince William's girlfriend Kate Middleton fell flat on her back Wednesday night at a charity roller disco in London, the Daily Mail reports.

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Wearing yellow hotpants, pink leg warmers, a shiny green top and roller skates, Middleton lay on her back for some minutes until a friend helped her to her skate-clad feet, the Mail reported.

Middleton was a co-organizer of the '80s-themed charity event benefiting Tom's Ward at the Children's Hospital in Oxford, England, and the organization the Place2Be, which provides counseling to youngsters.