 One day, Poseidon, filled with lust for Tyro, disguised himself as Enipeus and from their union was born Pelias and Neleus, twin boys.Tyro exposed her sons on a mountain to die, but they were found by a herdsman who raised them as his own.When they reached adulthood, Pelias and Neleus found Tyro and killed her stepmother, Sidero, for having mistreated their mother (Salmoneus married Sidero when Alcidice, his wife and the mother of Tyro, died).