Stream Stepsister from Planet Weird Online Free – Watch Full Movie from Home at 123Movies. . Megan's world is turned upside down when she hears her calm life with her little brother and single mum is about to change. She hears she's soon to have a stepfather and a stepsister. Megan thinks they're a bit weird and is determined to stop the wedding. She discovers they're actually even stranger than she thought - they're from another planet.