Kids' favorite aunt came to visit. Told me she has cushing disease. What should I tell my children?

Rarley hereditary. Usually due to a small mass in the pituitary gland in the brain that screats high level of special hormone that increase the production of cortisol from the adrenal glands. It cause multiple problems it increase weight , blood glucose , blood pressure causes osteoporosis. It is rarely hereditary and should not worry the kids that they may get it.
Not her fault. She can't help it if she's fat - she's "cushingoid". She needs treatment.