It was a family affair as rocker Phil Collins — who’s written the score for Disney’s “Tarzan,” which opens tomorrow — got his star on the Hollywood Walk of Fame Wednesday. Collins, 48, was joined by his fiancee, two daughters and one of his ex-wives for the sidewalk ceremony. “I’m pleased for my kids,” he said. “When they have their own children, they will ask, what did granddad do? And they will show them my star.” Hundreds of fans were also on hand, leaving Collins a little overwhelmed. “I am pitifully unprepared,” he said. “I thought it would just be me, a few people and the star. Silly me.”