My twins are about to turn 4 on the 11th of next month. The cat has been
around since long before they were born. They knew to keep their distance
from the cat at first, as she had no desire to interact with them. But
lately, she's mellowed out and let them (as well as our 18-month-old) pet
her. They're starting to get attached to her.

Well, I took her to the vet yesterday, and she possibly has diabetes. It's
complicated, but the bottom line is, she may have to be put to sleep, and
she may not. I am posting this to ask what other parents do when this
happens, especially at this age. If they were older, they'd understand it.
If they were younger, like my toddler, no explanation would be needed.

If I explain to them that she's very sick and has to be put down, then I
take her to the vet to do that, then they will get a negative impression of
doctors, and might also freak out whenever they or I get sick. I obviously
cannot sneak the cat out of the house and offer no explanation. It's gonna
be tough.