For example, my husband's blood type is
A, why does he know this? Because he thinks it was on his Army dogtag 30 years ago. Mine is O
. Why do I know this? Because I think my doctor told it to me once. If I had a paternity question I was trying to solve using blood types, I would certainly not rely on such poor evidence. I'd test again, and test him again and then talk to an expert, before I would use blood tests as the basis of accusations.