One day, Hades stole Persephone from where she was picking flowers and took her to the Underworld, where she would become his wife.
After nine days and nine nights of searching, the tenth dawn arriving, Hecate stood beside her, suggesting they see the sun god, in hopes he had seen who took her
Persephone? Where are you? It's been nine days!
Let us go to Apollo. Surely he had seen what happened.
Apollo had indeed seen who had taken her child. Hades had taken Persephone to the Underworld, leaving Demeter in grief.
"No less a theif than he, Hades, King of Darkness and robber of life itself."
In her sorrow, the land grew bitter, cold, and barren. She asked Zeus to make Hades return her daughter back to the land of the living.
Without my child, I have no care for man. Let them suffer, for no sorrow is my sorrow
Zeus agreed, on the condition that Persephone had eaten nothing while in the Underworld. When he found she had, he made a compromise to avoid her wrath. A month of the year for each pomograniteseed she ate.
She can return to you, as long as she ate no food from the Underworld
Thank goodness I gave her those seeds...
So she came and went without fail each year. In the months she was gone, the land was cold and bare, only to spring to life as she returned from the Underworld. The seasons corresponded with her presence.