Isis was perhaps the most important goddess of all Egyptian mythology. During the course of Egyptian history, Isis assumed the attributes and functions of virtually every other important goddess in the land. Her most important functions, however, were those of motherhood, marital devotion, healing the sick, and the working of magical spells and charms. She was believed to be the most powerful magician in the universe, because she had learned the Secret Name of Ra from the god himself. Isis was the sister and wife of Osiris, sister of Set, and twin sister of Nephthys. She was the mother of Horus the Child (Harpocrates), and was the protective goddess of Horus's son Amset, protector of the liver of the deceased. 