Not a twin, but I have a suspected narc brother (Br2).
My other brothers are fantastic as they have had their eyes opened to the shit I've had to endure at his hands.
For instance, not so long ago, he said that mum has issues with me that I have WRONGLY handled over the years. Mum has fired me some real evil/filthy looks over the years, to which I have asked her if I've done anything wrong or to upset/offend her. She has told me that "No, everything's OK" or "Everything's Fine" and I have given her more chances and opportunities to discuss any issues she has with me, like a rational, mature adult. She never took those opportunities to talk to me about any problem she may have with me.
TBH, I don't know if this is just my brother shit-stirring, but there are many times Br2 and mum have invited the rest of the family for dinner (all at the same time), yet they have left DH, our DC and myself out deliberately. Christmas is a funny one because my mum likes to make out she's a doting GM, but, so doting that she doesn't even know DS and DD's ages. She bought 7-8yo and 8-9yo clothes for DS and DD who are almost 11 and 12yo. She makes no effort at all and think that giving the DC a couple of pounds constitutes a loving relationship.
Everything with Br2 and mum is about money and image. It's funny, because Br2 recently gave me a lecture on how to be a moral person. A bit cheap coming from someone who was more than willing to cheat on his wife after less than 2yrs of marriage, bragged about over Sunday Dinner, which was then confirmed by our friend who he was willing to cheat with (she was the more moral person in that situation and told him it wasn't going to happen as he was married).
There is so much more to say about my family members, but it would take a year and a day to tell you everything.......as I'm sure the same goes for the rest of you on here.
On another note, does anyone actually just step back and watch the narcs in their family very slowly expose and subsequently destroy themselves without even noticing. By that I mean, do any of you watch the narcs make up some excuse for not speaking to someone because that person simply may have disagreed with them, but have made up some made-up, false,bullshit story about the person? When you stand back and see these people for who they really are and the good job they have done on many people (who think the sun shines out of the narcs arse), it's like waiting for that car crash to happen IYSWIM.