I watched a movie when I was a child, in the early 80s and I have been trying to find it, but I cannot remember the name. It was a movie about a family who crashed their aircraft in some woods. The monster/bad guy who lived far away in a cave took the parents, but for some reason did not take their son who was maybe around 10 years. I want to say the animals who found the child were monkeys who lived in the woods and took him in. Eventually they caravanned it to the cave and defeated the monster and freed his parents. Can you help me with the name of this movie?