There are DNA companies that focus on testing of parentage, however,
an autosomal test such as FTDNA's Family Finder or 23andme's Relative
Finder would be conclusive in confirming parentage as well (maternal
An Mt-dna test would also show whether someone else is a close
maternal line relative, but I don't think it would be as conclusive
in showing whether someone was say, a mother vs. sister or maternal
For the autosomal test, it would be very evident >from the amount of
DNA shared with a particular woman whether she was your mother or not
(or anyone else and their mother,speaking broadly).
However, I think it might be prudent to discuss this with an attorney
in your country (or wherever the friend is) , to find out what
constitutes proof, etc in a legal issue such as this one.
The trick of course is going to be getting her (the mother's) DNA if
your friend is in a legal battle with her (you need a good sample
from the puttative child and parent)!Steve Bloom
Central Virginia, USA
I would love your guidance please.