The Boy With Green Hair (1948)

Ann appears uncredited in a very short sequence about an hour into the film, during which Dean Stockwell (as Peter) has a dream in which he is confronted by a group of war orphans who change his outlook on the experience and meaning of having green hair. She has several lines in medium shots, and holds an infant through most of the scene. Her concern for the infant is apparent as she keeps glancing down at it during the scene. Ann would have been right around her 12th birthday at the time of filming.