Before he passed away, our older Siamese coexisted with turtle just fine, would hang out in the side yard to get sun together.
Then we got a feisty Siamese kitten. His favorite morning game was to go and find turtle in the flowers where it wold hide. Then he would pounce. Probably could not hurt turtle, but we felt bad about it.
Kittens will be kittens.
When I was pre-school aged (late 1940s), we got a little turtle with red markings on both sides of its neck. It was about the size of a 50 cent coin. Kept it in a large glass bowl with rocks and water, and fed it raw hamburger and lettuce.
That turtle won the turtle race at my school carnival when I was in 1st grade. Seems about 15 of us kids all had turtles about the same size, so it must have been a fad at the time.
Years later, it grew too big for the bowl so we put it into the bed along the back of the house. The bed was full of mint and shady, and we watered the area every day.
The turtle would dig a burrow in that bed and basically hibernate during the cold weather. Each Spring we would look for it in the mint bed and would find it healthy and larger. ....Last time we saw it, it was about the size of a salad plate at a nice restaurant. Don’t know if it died or just decided to move on.