What to call FIL partner?

My DH parents spilt up when he was 10 or so. The reason they split was due to FIl partner.So there has always been a bit of friction around this issue. Now that we have DD, I don't know what to call FIL partner, DH says no way to Nanna etc because DD has 2 real nannas already (fair enough) but FIl partner referrs to herself as Nanna when I talk to her on the phone (they live in the country so I dont see them alot) What do I do? and what do I call her that will make everyone happy and not offend anyone? please help

how about nannaX eg if her name is Joan call her nanna Joan

hi
mine and DP's parent are all seperated. his mum has remarried. her hubby gets called Grandad but we dont want this as he hasnt had children and doesnt feel right to us for him to skip that step and have a grandchild. my parents partners are called Grandad Bill (mums partner) and Nanni Leigh (dads partner).
we have tried telling MIL that we want her hubby to be Grandad Bob but they dont listen to us. so when we talk to DD about him thats what we use and hope that as she grows older she will call him that

MIL and FIL are divorced and have both re-partnered. MIL's partner gets called Grand Pete (his name is Peter) and FIL's wife gets called by her first name. Lucky for us neither of them wanted to be called granddad or nanna or anything like that. Both said that the kids already had their grandparents.

Pete got his name from friends of ours, they did something similar. We decided that he needed to be more than just Pete but Grandma and uncle Pete would cause confusion later on. FIL's wife doesn't have a special name yet because we haven't found one that fits.

On the other side my mum tried to get her partner to be called Papa Tony but I wasn't having any of that. I don't really like the man and there was no way he was having a special name so DS just calls him Tony if and when he sees him.

My parents are divorced and they are both re-married, i truly dispise my mothers Husband.. and he tries to get my son to call him "Poppy" it makes my stomach turn!! I just tell him he isn't my father so there for he isnt my sons "Poppy" I don't have much to do with my dad but there is a snow flakes chance in hell My mothers new husband will ever be "Poppy" it makes me wanna be sick just thinking about it.

When I was a kid my mother had a step mother that she really didn't like, she refused for us to call her nanna or grandma and my aunts also refused to let their kids call her that so we used to call her 'Aunty' ... she seemed happy with that and it worked well. I now have a similar situation with my kids ... My DP's mother and father split when he was 10 ... it is an extremely weird situation as his parents new husband/wife used to be married to each other, I find this really odd, but anyway I too don't want them being called nanna and pop because my kids have 2 nannas and 2 pops so they just call them by their first names