Taylor Lautner Bowled Over At 21st Birthday Bash

_Actor Taylor Lautner celebrated his 21st birthday by bowling with his celebrity pals Kristen Stewart_, __Ashley Benson and Patrick Schwarzenegger.

The hunk, who turned a year older on Monday (11Feb13), marked the milestone in Los _A_ngeles on Saturday (09Feb13) by enjoying a night out at posh bowling alley Lucky Strike.

A source tells UsMagazine.com, "Taylor was super nice, very polite. Everyone was having a blast... (and) super into the bowling. (Lautner) is really good."

His Twilight co-star Stewart arrived at the event just after midnight in a backwards cap and ripped T-shirt, and an onlooker says the 22 year old had a good time catching up with her former onscreen love interest.

_A_n insider adds, "She was being fun and social, bowling and high-fiving. She and Taylor definitely seemed to be good friends and she was living it up."

Stewart, Pretty Little Liars beauty Benson, and _A_rnold Schwarzenegger's son all then sang Happy Birthday to the star before departing around 1:30am local time.