Paternity test query - 99.999999% probability of paternity that my partner is father of my child. can it be wrong if another potential father is related? (father/son relationship). is my partner the dad?

I am thinking you would know if partner could be his DAD. In general children & parents share 1/2 of their genes. 1/2 from genetic mother and 1/2 from genetic father. Thus you son's DNA will be about 1/2 different than your father's and the 99.999999 % prob that your "partner" is the father of the child you are carrying. If genetic tests were done on both you and your "partner" and you then OK.

The son has only 1/2 the genetic material from his father. The cited match says there is only 1/10 million chance it is not the listed match no matter what the possible relationship of the potential donor. You keep asking the same question looking for a different answer, which will not come. I suggest you find a life coach & learn some stress management. You will need it.