In Greek Mythology, Poseidon is the Olympian god of the ocean, horses, storms and earthquakes.
Poseidon was born to Kronos and Rhea, the king and queen of the Titans, the primal gods who ruled the universe. Kronos heard a prophecy that one of his children would overthrow him; to prevent this prophecy from coming true, he swallowed his babies when they were born.
Because the children were immortal, they survived being swallowed and grew up incarcerated in their father's stomach. One of Kronos's children, Zeus, had been hidden away by his mother and training out of his eyes.