Demeter and Persephone where out collecting flowers one day.
Persephone left her mother in search of more flowers and suddenly Hades lord of the underworld came upon her and took her away
Demeter heard Persephone's cry but could not find her at that moment Hecate came looking for Demeter as she had news.
Demeter and Hecate then went to see Helios who told them that Zeus was the one that allowed Persephone's kidnap. Demeter was so shocked by this she vowed never to return to Olympus until she got her daughter back.
Zeus heard this and ordered Hades to give Persephone to her mother. Hades agreed but just before they left he gave Persephone some pomegranate.
Alas, Persephone was reunited with her mother, Demeter asked her "Child, you didn’t eat any food while you were down below, did you? Persephone said "yes I had pomegranate" Demeter then started to cry as her daughter would stay in the underworld for a 1/3 of every year.