Hera was the queen of the gods, and the goddess of marriage. 

She was one of Zeus' three sisters. She was also his wife. She was very jealous. She kept a close eye on Zeus. Hera was rarely nice to the many children Zeus had by other mothers. There are many myths about Hera's jealously, anger, and revenge. 

Other myths talk about Hera's servant, Argus. Argus had 100 bright eyes all over his body. He was a great guard because he never closed more than half his eyes at one time!