An odd, sweet, mysterious, soulful, warm little film about loss and connection, “Petite Maman” raises a few more questions than it answers, but sometimes explanation is overrated. This is one of those cases. Nelly (Josephine Sanz) is an 8-year-old who has just lost her grandmother. She accompanies her mother and her uncle to her grandma’s house while they clean it out. On the way there, from the backseat, Nelly offers her mother a snack, a sip from her juicebox and a hug. The two are more connected than they even know. Nelly, a deeply independent soul, asks questions of her mother and her uncl…