What do you (or rather your children) call your children's grandmothers? Both DM and MIL are Scottish.
DM's mum was Mama (her father was Papa) and Dad's mum was Granny (I never knew his father). DH called all of his grandparents 'Gran/Granpa+Surname', as in Gran Smith vs Gran Jones, which I find a bit weird for some reason!
I quite like the idea of continuing the 'Mama' tradition, but DM is already 'Granny' to other grandchildren, and I don't think MIL will like it (and DM might not like that being used). I don't really mind that much, and we will ask them their preference when the time comes, but I'm just curious as to what other people like/dislike and what combinations you have for either side...