If the father of a child is deceased is there another way of getting DNA testing

Question:From the mother of the deceased father?

Best Answer - Chosen by Asker: From the mother of the deceased father?

I'll admit, yours is a unique situation.
If both you and mom are in agreement on this, I'd contact one of the DNA testing companies, and ask. If you have another son, it may be possible that his dna would be CLOSE ENOUGH to show a probable relationship, since siblings are very close in terms of their genes. It would be way different if you wanted testing, and mom was against it. I don't think you could get a court order, as in usual paternity issues.
I think this would be worth making a few phone calls, since I don't have an answer on this (maybe someone else does).
http://www.ptclabs.com/who_is_tested.htm
HA! this site says yes, it can be done. You will also want to check out what different companies say, to make sure you are getting a bargain.. but looks like on the right track.
Estate or otherwise.. I wish you the best in learning that you indeed have a granddaughter, and that it leads to a warm relationship for all involved.

the mother of the deceased would only share 1/4 of the childs genes. i don't know that that would be enough to be conclusive. what's the nature of the dna test? is it paternity? could you possibly rule out another individual to determine?

There are so many DNA testing companies out there, I am certain that at least one of them could help you. A child will have 1/4 of its DNA from EACH grandparent; 1/2 from each parent.
Males do NOT pass mtDNA on to their children; it is done ONLY through the female (and yDNA is provided only by males). So, if you are seeking DNA evidence to the GRANDMOTHER, the father of the child is not needed.

Sibling Testing

If the father's or mother's DNA is not available for testing (see forensic paternity section for alternative sources of DNA) we can determine a genetic relation by testing the siblings or other close genetic relative. A sibling test is a more complicated statistical analysis than a paternity test and may or may not give you the answer you need to answer questions about paternity or maternity. A full sibling test will indicated that you are likely or unlikely to share a common mother and father. A half sibling test will indicate that you are likely or unlikely to share a common parent (mother or father).

Other relatives.

Does this father have any other living children? You could try that route.

Siblings and extended relatives can be used to determine hereditary links. The company doing the test will confirm who/how many links to be made to be sure.

Genetically, you passed your X chromosome to your son and his father gave him a Y chromosome. Your granddaughter would have your X chromosome as well as one from her mother. A reputable DNA testing company can test both X DNA strips and break apart which was from you and which was from her mother. The Y chromosome from your husband was lost. You would have a direct genetic link to the child if she is your granddaughter, so there is more than enough to test. They might not be able to prove if one of your sons was her father over another, but they could prove you are the grandmother.