Kristen Stewart attended her "Twilight" co-star Taylor Lautner's 21st birthday party at Hollywood's Lucky Strike Lanes bowling alley, E! News said.
"He didn't want people to sing 'Happy Birthday' to him,'" a source told E! News, "but his friends wanted to do it anyway."
"Twilight" leading man Robert Pattinson, Stewart's real-life boyfriend, is in Australia working on the film, "The Rover."