Heracles was a son of Zeus and Alcmene. A major factor in the tragedies surrounding Heracles stem from Hera's hatred of him; as the wife of Zeus she often hated his mortal offspring because they were living proof of Zeus' constant affairs, and she especially hated Heracles. While Alcmene was pregnant with Heracles, Hera, who was already informed of Zeus' adultery, persuaded Zeus to swear an oath on the night Heracles was to be born that the child born that night to a member of the House of Perseus would be High King. Once the oath was sworn, Hera hurried to Alcmene's dwelling and slowed the birth by sitting crosslegged with her clothing tied in knots. She would have permanently delayed the birth had she not been foiled by Galanthis, her servant, who told Hera that she had already delivered the baby. Hera turned her into a weasel and forced her to give birth by laying eggs through her mouth.