Theater reviews: "Elephant & Piggie's 'We Are in a Play!' " and "Lyle the Crocodile."

Holiday parties of all descriptions are in the pipeline around the region. But few festive gatherings will be as zoologically notable as those in two children's musicals, "Elephant & Piggie's 'We Are in a Play!' " at the Kennedy Center Family Theater, and "Lyle the Crocodile" at Imagination Stage.