The Water Horse: Legend of the Deep

Set in Scotland during World War II, our hero is a young boy who pines for his sailor dad, away with the war. His mom is housekeeper at a large mansion next to Loch Ness. One day, he finds a mysterious large egg, which later hatches into a little lizard-like monster. Keeping the monster as a pet becomes increasingly problematic, as it grows very fast. Soon it is an adult, and still his pet, and they have lots of great adventures together. Meanwhile his mom is dealing with two very different suitors... an army officer, and the new handyman.