Robert Pattinson `leads celebrations` for Kristen Stewart`s 21st

Twilight cast and crew threw a private party at Rockwell's Bar & Grill in Squamish, Vancouver, for the actress, who blew out the candles on a 'simple chocolate cake' at around 10pm according to Us Magazine.

Everyone tucked into oysters before boyfriend Robert kicked off the singing.

'Rob led the crowd singing for her, and you could tell she was so embarrassed but in a cute way,' a source said. 'Everyone was in a good mood, but it was a bittersweet night (as filming is almost complete).

'Rob and Kristin were together all night. They held hands and he kissed her cheek a bunch of times.'

A second insider added that her cast mates all pitched in to buy her a motorcycle.

'Rob was so excited for Kristen and they each took turns riding it,' said the source. 'Kristen learned to ride a dirt bike in New Moon so they thought it would be appropriate. Rob was supervising as she sat on it to make sure she was ok. They looked like they were having a great time, and it will be something they can really enjoy.'