Celebrity guests included likes of Joaquin Phoenix, Olivier Martines, and Kirten Dunst.

The magazine reports that the pint sized billionaires went through great lengths to ensure that no would be crashers made it into their exclusive soiree. They closed down the street in front of their house and hired a security team to scour the area.

Luckily for us gossip whores, there's always an "insider" ready and willing to reveal all the juicy happenings.

"It was really heartfelt but a great time," a source told US. "Everyone danced all night."

Just before midnight, Ashley made a speech, "I would like to thank everyone who came out tonight to celebrate with me… I hope we will have many more happy memories this next year."

She then spoke candidly to her twin, "No one could understand me the way you do… Nobody could relate to me the way you do. In fact no one could even tolerate me the way you do!"

Considering the girls made their first billion dollars before the age of 15, what's the right to order a Cosmo at the bar really mean to them? Anyway, happy belated birthday girls!

BY EMMIS RODRIGUEZ