Sonny Boy (1989)

A small-town crime boss accepts delivery of a stolen car, only to find there's a baby in the back-seat. He and his transgender wife cut out the boy's tongue and raise him as a mute accomplice in their crimes. When the grown "Sonny Boy" escapes and tries to make contact with the outside world, the attention he draws to his warped family results in darkly-humored mayhem.