Brunneria - my point is that all she needed to do is to tell both her children that she has developed a chronic condition that may be hereditary and they need to get blood tests annually (or whatever the recommendation is). She said nothing to us about it.
I just cannot understand how this cannot of been part of the thought process.
As soon as I was diagnosed I told my brother that he and his children should be tested. It is one of the first things that occurred to me.
I am not entirely sure I agree with your assertion that everyone is equally blameless when it comes to developing diabetes. If you are pre-warned that you are high risk and ignore advice and develop the condition, this is surely completely different from having no awareness whatsoever and develop the condition through ignorance to the risk factors.