Old man finds a baby in a fast running stream.Rescues the baby and takes it to his home. He lives in a giant hollow tree. Story goes that mother and baby were on train, it was raining and bridge washed out and the train wrecked. That's how the baby got in the water. Baby grows up with old man as his father. Eventually, his parents appear. Don't remember the outcome. Does anyone know the name of this movie? Probably late 30's early 40's.

The Enchanted Forest (http://www.imdb.com/title/tt0037672/reference)