KE$HA was left red-faced after playing at a private party and wishing the host a happy 16th birthday - without realising she was attending a 12-year-old girl's bat mitzvah.
The TIK ToK singer was reportedly paid $50,000 (£33,000) to play a two-song set at the lavish bash at New York's Cipriani 42nd Street venue, which saw revellers enjoy ballet dancers suspended from ceilings and expensive candy dished out on arrival.
After performing her hits, Ke$ha addressed the crowd and wished the girl host a Sweet 16th, which was met by a sea of bemused faces, according to New York Post gossip column PageSix.
A source tells the publication, "Everyone flips. Then Ke$ha wishes the girl a happy Sweet 16, and people clap, but with puzzled looks on their faces. It's not her Sweet 16. It's her bat mitzvah."