Read more: Lady Gaga to wear new Irish designer’s work at Grammys?

The eccentric pop star celebrated turning 25 with her family and close friends - including her boyfriend Luc Carl, Kate Hudson, Fergie, Cindy Crawford and Adam Lambert - at Los Angeles’ LA Cita Mexican restaurant, and was showered with gifts, including the saucy present.

A source said: "Gaga got diamonds from one anonymous guest while another had a sex doll made for her – its piece de resistance was a huge penis."

The singer hired out the whole bar and was also treated to a berry-covered , Jack Daniel’s whiskey and champagne.

After she cut the cake the star, whose real name is Stefani Germanotta, took to the stage for a live performance of songs by Madonna and Motley Crue, as well as her own hit 'Born This Way', with the restaurant's Mariachi band.

An onlooker told "She was onstage for most of the night performing for all her friends. No one knew she was going to go up there and perform with them, I think she just loves to be on stage and doing what she does so well."

Another guest of the wild bash was Gaga's mum Cynthia, who was reportedly left blushing by her daughter's wild antics.

The spy said: "Gaga, who treated her tequila-swigging guests to a tipsy rendition of 'Born This Way' backed by the restaurant band, was on serious form.

"Adam Lambert got a little over-excited while dancing and bashed his head on the ceiling. And Gaga's mum Cynthia looked red-faced at times – she kept muttering, 'Stefani!' under her breath."

Read more: Lady Gaga to wear new Irish designer’s work at Grammys?