Hercules fell from Olympus. A couple from the normal world found him and took him in. he lived a good childhood, but he often got shamed for being really srong.
Hercules adoptive parents tell him he is adopted. They tell him when they first found him he had a medal with the symbol that represents Zeus. He takes this as a sign and goes pray to a statue of Zeus and the statue comes alive to tell him that he is a demi-god and son of Zeus.
Zeus gave Hercules the opportunity to learn where he came from and he did not refuse.