Last story: A boy who is very weak gets killed by a dragon and he is your ancestor's dog.
Once upon a time, there was a dog. The dog was killed by a dragon. The dog made a wish when it was getting burnt to death; a wish that would make his decendants always be rich. However satan got his hands on the wish first and edited it so that his decendants would have bad luck forever. Satan dressed up as an angel and delivered the edited wish to god. God liked the wish and accepted it so that is why your ancestor's dog's descendants always have bad luck and get burnt to death by a dragon when they are young.