Sorry to hear about your dad.
My father and uncle both lost limbs to diabetes in their elder years. Both were very religious, too. But still with the drinking, smoking, etc.
Kind of a native thing, the diabetes. Lost my half-native grandfather to diabetes, too.
I am currently doing the geneology thing to find our tribe for my daughter. She wants a tattoo, so I will compromise if she gets one that means something to the ancestors.