Not necessarily true. I have two children with type 1 and there's not a diabetic anywhere in the family.
My brother is a biophysicist working on cancer vaccinations, meaning he knows many in the field. He tells me they're starting to believe that type 1 is actually an environmental virus.
That said, the Wise Latina should know after a lifetime with the disease how to keep her numbers in check. And she should drop the weight because that could also lead to type 2.
I said genetic.
I did not say heredetary.
Not exact interchangeable terms.
Virus as cause of Type 1 has been suspected for a long time.