Rātā's sons by Tonga-rau-tawhiri were Tūwhakararo and Whakatau. In other accounts, their parents were Tūhuruhuru and Apakura. In other accounts still, Apakura as Tūwhakararo's wife threw an apron or girdle into the ocean, which a deity named Rongotakawhiu turned into Whakatau. The boy was taught a handful of magical secrets by the deity, and he was capable of living under the sea. As Whakatau's brother, Tūwhakararo had been murdered by the Āti Hāpai (or Raeroa) tribe, so the former avenged him by gathering an army and slaughtering the offending tribe. This is one event that was said to trigger migrations from Hawaiki.