What do you think I should do in this situation?

[Wexflyer]

The truth needs to be known.

This is unconscionably dogmatic.

The truth for OP's grandmother is that her father was the man who reared her, who put the food on the table, who kept the roof over her head, who was there for her for 30 years until he died. That is her truth.

Telling her 71 years later that, well no, he wasn't your father at all may damage her psychologically, and risk their relationship. Does OP want to risk that? For what? What will OP actually gain by telling her grandmother what she has learned? In terms of genealogical information, nothing.

[Cell]

Is your mother your  said nan's daughter?
If she is your nan's daughter,  what are her thoughts on the matter? 

Me, I wouldn't  tell my own  Nan if she was alive, if your Nan wanted to DNA test she would. It is up to you and your mum, you know your Nan,  we  certainly dont .

Interesting some of you wouldn't want  know if it was you in nan's position.
Nan has half siblings that she doesn't know about. My parent is in the OPs  nan's position (  my parent has a half sibling that they don't  know about)

I am in a extremely  similar position to your mother, except  it is  my grandfather who fathered an illegitmate child and not the other way about( my granddad fathered an illegitimate child overseas when he was in he army, an affair) .
I have chosen  not to tell  my parent that they have  a living half sibling. It is an extremely, extremely difficult decision to live with!  And anyone  who has ever been in the same position   will know that.


 I have been living with my decision of not informing my parent for just  over two years, it is very  hard to live with it , its not a easy decision.
That's  why I asked you, about  your  mother's thoughts, as she is closer to the situation  than you are, . Your nan's half sibling's are your  mum's half uncles/ Aunts.

I am in contact with my  half uncle ( they took a DNA test , it was how I intially found out , we both highly matched to eachother ,and it was pretty obvious.  We match very high, almost half sibling level.) .

I  assume your nan's  half siblings haven't  taken a test,  and don't  know about your mother or your Nan? ( as your mother would be highly matching to them, it would  be pretty obvious  to them that your  mother must be their half niece).

I 100%  think it's your and your mother's  decision, not strangers, and certainly not one's who have never been in this situation.
( I received flak off someone here   for making the decision  not to tell my parent that they  have a living half sibling )

It is YOUR and YOUR  MUM'S  DNA ,  it is therefore your  and your mum's decision.
For some  who think  "the truth  should be known". It is not your Nan, or  your  close family they will be hurting ,or not hurting. If we all spoke the truth,  when some of the truths can gain no good and just  hurt  the people that you care  deeply about -  what a world it would be eh.

Best of luck to whatever  you  and your mum decide, only you  and your mum  know what is best in your own family's situation ,  I know it is not an easy decision either  way  - It's  something  I have to live with everyday  not telling my parent and spend  many sleepless nights  over it - to tell  my parent, it would extremely hurt  them.
 Very Kind regards

[Pfig]

I had a similar situation although not involving DNA. 

My late mother knew her mother had given her up in the early 1930s when she was a baby and had no further contact with her.  There was no father's details on her birth certificate and my mother had no interest in knowing anything about her background. 

Over 20 years ago I managed to trace and make contact with a cousin of my mother's and through her found out that my mother had a half-sister who was still alive and who lived within a couple of hours drive of my mother's address.

I kept that information from my mother, although it wasn't easy and I had a certain feeling of guilt about it.  It was only 6 years after my mother died that I told my siblings. 

I also waited until my mother had died to make contact with the half-sister who welcomed me and was able to fill in some gaps in my family history.  My siblings were very surprised that I'd kept this information private for so long.  They, however, had very little interest in the whole thing.  Everyone is different.  It matters to some people and not to others. 

I was also able to obtain photos of my grandmother and the likeness between her and my mother was startling.  It did cross my mind that she might have wanted to see a photo of her mother but something just made me put this to the back of my mind and try and forget about it.  It became easier as the years went on.

There was no way I would have ever told my mother and she had made it clear that she wasn't interested.  Had she shown an interest and asked me then, yes, perhaps I may have told her.

It was enough for me to know where I had come from and to have family photos.  It would have been of absolutely no benefit to upset my mother by sharing this with her.

[SouthseaSteel]

You may also need to factor in the risk that your nan may somehow learn of this from somebody else and not you.  Theres a lot less thoughtful people than you out there on DNA platforms.

[AnnaBme]

In "FAMILY TREE" which is more important to you "FAMILY" or "TREE"?

[jimbo50]

In "FAMILY TREE" which is more important to you "FAMILY" or "TREE"?

Yes. well put, AnnaBme. Some people on here are treating their family as a name on a piece of paper. Also, I would endure anything not to hurt any one of mine.

[louisa maud]

You asked our opinion and you have had various replies, I think you should tread very carefully, not always should the truth be told on these sort of delicate questions, I wish you the best of luck in whatever choice you take

LM

[Jackiemh]

I agree with Louisa Maud. It is really your decision but not an easy one.
If it was me, I don't think I would tell but would try to be prepared if someone else spilt the beans.
Good luck, Jackie

[Wexflyer]

In "FAMILY TREE" which is more important to you "FAMILY" or "TREE"?

Hear hear. This is the fundamental issue here.