How did Ursa Major and Ursa Minor come from?

Ursa major and Ursa minor are actually the goddess Caliste and her son Jagas that Wang Yusi likes. Because of the jealousy of Hera, Calliste was turned into a bear. When other Yamazawa goddesses came to see it, they found that only one bear was missing. Divines thought the bear had eaten her, so they drove her away and gave Jaggers to a shepherd for adoption. Christie, who was turned into a big bear, stayed with her son until he grew up. Yus, the king of heaven, looked at Yagas from the sky and found that this bear was different from other bears. She knew she was the goddess of Yamazawa, but she couldn't break Hera's spell, so she turned Yagas into a bear. Jaggers recognized his mother, and Yus, the king of heaven, took them to heaven and called them big bears and little bears. Hera was very angry when she saw two new constellations placed between the stars, but she couldn't interfere. So Hera went to see Poseidon, the sea god, and asked him to promise not to let these two constellations rest on the seabed like other constellations during the day. Therefore, Ursa Major and Ursa Minor will always revolve around the North Star. It is impossible to fall below the horizon and stay in the sky forever.

I simplified it and didn't say anything specific. This story is too long, basically.