Cronus (Kronos) and Rhea are pivotal Titans in Greek mythology—children of Uranus (Sky) and Gaia (Earth).
Children (the first Olympians): Hestia, Demeter, Hera, Hades, Poseidon, Zeus.
Myth: Cronus, fearing a prophecy that a child would overthrow him, swallowed each at birth. Rhea tricked him with a stone wrapped in swaddling for Zeus. Zeus grew up in Crete, returned, forced Cronus to vomit his siblings, led the Titanomachy (10-year war), defeated the Titans, and became King of Gods.
Iconography: Cronus: scythe/hourglass. Rhea: cornucopia, lions, turreted crown. Worshipped as primordial time/fertility deities.