Cancer is the Zodiac sign for those born between June 22 and July 22. The symbol for Cancer is a large crab.
The model for Cancer is a crab who served Hera. This story is closely tied to that of Hercules’ twelve labours. Hercules, being the son of Zeus and a human woman, was hated intensely by Hera, the wife of Zeus. Thus, she made him made, causing him to kill his family and being punished by having to undergo twelve near-impossible challenges. One of these was killing the nine-headed monster, the Hydra. Hercules had already accomplished the first task so easily that Hera wanted to distract him. She sent a crab down to the human world and commanded it to attack Hercules. The crab crawled all the way to the battle scene and ferociously bit his toe. But Hercules simply kicked the crab, causing it to get crushed and killed instantly. Hera felt sorry for the crab and sent its body into the heavens where it became a constellation. This is quite possibly the saddest death in all of Greek mythology.
(Part of the Zodiac series: https://jineralknowledge.com/tag/zodiacs/?order=asc)