I used to think tortitude was just a myth, then I compared the quote below and compared it to Kasey.
To quote it, with my comments in brackets;
"In addition to their distinctive coloring, torties also have a reputation for unique personalities, sometimes referred to as “tortitude.” They tend to be strong-willed (Yes for Kasey), a bit hot-tempered (Yes for Kasey) , and they can be very possessive of their human (Yes for Kasey, I belong to her). Other words used to describe torties are fiercely independent, feisty (Yes, yes for Kasey) and unpredictable (No). They’re usually very talkative (Yes for Kasey) and make their presence and needs known with anything from a hiss to a meow to a strong purr (Yes for Kasey). These traits are stronger in tortoiseshell cats than in calicos – it seems as though these traits are somewhat diluted with the addition of more white to the color scheme."
I know torties are a color, not a breed and that individuals can vary in temperment, but this is pretty close to the personality of "my old girl"