Saw this the other night... Still gives me feels, classic movie. Researching the past, I found out the horrible truth about Duckie I think, Judith Barsi.
Straight forward, she had some condition where it stunted her growth and she kept the childish look. The problem was her father was into some 10x

. I guess she got beaten repeatedly by the father, cause he was a major alcoholic and severely was jealous of his own daughter. He ended up killing his wife and Judith and tried to burn the bodies before he offed himself. Really fukking tragicness.