What do you call the significant others of older family members?

[Anonymous]

My grandmother passed away last year and now my grandfather has a girlfriend. My question is what should I tell my young daughter to call the girlfriend? I assume I will just call the girlfriend by her first name, and normally would tell my daughter to call her Miss First Name. But my husband wonders if we should call her "Aunt," "grandma," or something else like that. That seems strange to me because she isn't an aunt or a grandmother (at least not yet - who knows if they will end up married).

Any thoughts on this? I know it's dumb but I don't want to offend anyone or confuse my daughter, who still remembers her grandmother and this will be the first time my daughter meets the girlfriend. For now, I plan on just using the Miss First Name plan unless the girlfriend says otherwise.

[Anonymous]

Depending on her preferences, she might prefer Ms or Mrs Last Name.

[Anonymous]

Ask her what she would like to be called.

[Anonymous]

I had this happen to me. We call her Ms. First Name.
She is not, grandma. She has no issue with it.

[Anonymous]

PP again. They actually married - and after 25 years of calling someone else grandma, and it was no more expected for the children to call her Mom than it was for grandchildren to call her grandma.