Jupiter, the king of all the Roman gods, had three sisters. 

Hera, his wife and sister, was the goddess of marriage and the queen of all the gods. 

Vesta, another of his sisters, was a much loved goddess by the woman of Rome - Vesta was the goddess of home and hearth. 

His third sister, Ceres, was in charge of the harvest. If Ceres was upset, the crops could die. Everyone, gods and mortals, worked hard to keep Ceres happy. What made her the happiest was enjoying the company of her daughter, Proserpine. 

As the story goes ....

Proserpine had grown into a beautiful young woman. She had a smile for everyone. One day, while picking flowers in the fields, Pluto, her uncle, the god of the underworld, noticed her. Pluto was normally a gloomy fellow. But Proserpine’s beauty had dazzled him. He fell in love instantly. Quickly, before anyone could interfere, he kidnapped Proserpine and hurled his chariot down into the darkest depths of the underworld, taking Proserpine with him.

Locked in a room in the Underworld, Proserpine cried and cried. She refused to speak to Pluto. And she refused to eat. Legend said if you ate anything in Pluto, you could never leave. She did not know if the legend was true, but she did not want to risk it in case someone came to rescue her. 

Nearly a week went by. Finally, unable to bear her hunger, Proserpine ate six pomegranate seeds. It seemed her fate was sealed. She would have to live in the Underworld forever.

Meanwhile, back on earth, Jupiter was worried about the crops. The people would die if the crops failed. If that happened, who would worship Jupiter? He had to do something. Jupiter did what he often did. He sent Mercury, his youngest son, the messenger, to crack a deal, this time with Pluto. 

Even as a baby, Mercury was great at making deals. Everyone knew that. But this deal might be the challenge of his life. His uncle Pluto, king of the underworld, was really in love. This was no passing fancy. 

When Mercury heard that Proserpine had eaten six pomegranate seeds, he had to think quickly. The deal he made with Pluto was that if Proserpine would marry Pluto, she would live as queen of the underworld for six months out of the year. However, each spring, Proserpine would return and live on earth for the other six months of the year. Pluto agreed. Jupiter agreed. Proserpine agreed. And finally, Ceres agreed. 

Each spring, Ceres makes sure all the flowers bloom in welcome when her daughter, Queen of the Underworld,  returns to her. Each fall, when Proserpine returns to Pluto, Ceres cries, and lets all the crops die until spring, when the cycle starts again.