Directed by Richard C. Sarafian, this 1969 British children's film stars Mark Lester as a young boy, unable to speak, who befriends both a wild colt with blue eyes and a falcon named "Lady". The cast also includes John Mills, Gordon Jackson and Sylvia Sims.
The little boy is described as psychosomatic youth, but this is a 1969 movie. We would call him nonverbal/autistic now but he does become very upset at one point in the movie and Lady the falcon is tethered to his hand. She becomes injured when he becomes upset and runs uncontrollably.
Not abusive, but this movie was made in a time where people did not understand or were even aware of autism… ignorance of the times. There are times when the main character is not treated well, but also, little is known about his condition.