Romance Report for April 12: K.Stew's Bittersweet Birthday and Much More

By Kat Giantis

Brace yourselves, Twi-Hards, because Bella can now legally imbibe. Us reports that Kristen Stewart rang in her 21st birthday Saturday night with a low-key, private shindig in Squamish, British Columbia, where she's wrapping production on "Breaking Dawn." On hand to help her celebrate the milestone at Rockwell's Bar & Grill: rumored honey Edward Robert Pattinson and several members of the cast and crew.

"Rob led the crowd singing for her, and you could tell she was so embarrassed but in a cute way!" relays a spy. "Everyone was in a good mood, but it was a bittersweet night [as filming is almost complete]."

Robsten didn't seem bothered by those breakup rumors that surfaced last week, and they stayed close during the festivities. But as usual, they kept the PDA to a minimum.

"Rob and Kristin were together all night," adds the snitch. "They held hands and he kissed her cheek a bunch of times."

Maybe R.Pattz was just buttering K.Stew up so he could try out the brand new motorcycle that the attendees chipped in to get her.

"Rob was so excited for Kristen, and they each took turns riding it," says an insider (see blurry birthday pics here). "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!"

RELATED: See Rob strike a pose for Elle