Cronus, the titan

Cronus/Saturn was a powerful titan married to Rhea. His sons and daughters were Zeus/Jupiter, Hera/Juno, Poseidon/Neptune, Demeter/Ceres, Hades/Pluto and Hestia/Vesta. His parents told him that he would loose his power because of one of his sons, so he ate them just after Rhea gave birth to them. (Image: Wikimedia Commons)

Saturn devouring his children, by Francisco de Goya.

Tired of this, Rhea gave him a rock instead of Zeus/Jupiter. He grew up and made him regourgitate his children, who were now adults and fought with him against the titans on the Titanomachy. The titans lost and Cronus was imprisoned in the Tartarus. (Image: Wikimedia Commons)

Cronus devouring his child, by Pietro Muttoni.

Source: Encyclopedia Britannica