In Human Milk in the Modern World by Derrick and Patrice Jelliffe,
there is a photo of the painting by Rubens entitled "The Milky Way".
It is explained ," Hera, wife of Zeus, about to nurse her son
demonstrating an unphysiologically exuberant let-down reflex, which
should be bilateral."  : ) 1978 Fig.2.11 p. 25