DNA Mystery - Please Help

[cmower]

Thanks again Davidft!  I'm going to take your advice and try contacting A.  I'm also going to see if my cousins will get tested.  Fingers crossed...

[hurworth]

My mother - 6 cM / 1 segment
My mother's sister - 0 cM / 0 segment
My sister - 82 cM / 7 segments
My brother - 127 cM / 7 segments
Me - 113 cM / 8 segments

Please let me know if there's something I'm leaving out.

From this you are clearly most closely related to this person via your father.  They also appear to be distantly related via your mother, but 6cM is getting to the level that you can't be confident that it's a real match.

[sugarfizzle]

Another suggestion, you may already have done so.

Upload your families DNA to gedmatch, familytreeDNA, myheritageDNA.  If your match is willing to do so also, you will be able to see where you all match.

Consider asking your cousins to test at Ancestry, as well as yourself and your mother. Then get your cousins to upload to the other sites as well.

Regards Margaret