Background:

The daughter of Junior Officer William Winchester and his ex-wife Wanda Wallace, Kate remained with her father after her parents divorced. When she was a child, her father was abducted by aliens and gave birth to Anthony Winchester.

Though Kate always had aggressive tendencies, it got worse when she was a teenager. She defeated multiple Sims in a fight, and some people believe she is responsible for the death of Morgan-Fay Goodman, who was mauled by wolves. As a result of Morgan-Fay's suspicious death, she got into a fight with her brother, Major Goodman, who would go on to become one of her most tenacious enemies.

During that time, she also went steady with Jonathan Gunner, a fellow student. The two eventually got married as adults and had four children : twins Emily and Erin Gunner, a third daughter named Taylor and a son named Dwight.

Unfortunately, Jonathan became a collateral victim of the feud between his wife and Major Goodman ; he got into a fight with Major's wife, Evi-Lyn Goodman, then mysteriously disappeared. His whereabouts remain unkown. Because of this, Kate hates the Goodmans and wants revenge for what they did to her husband, whatever it was.

Now an army Commander, Kate wishes to become a General. She spends most of her "free time" spying on the Goodmans or working out.