It all gets very complicated.
When I was a child :
Mother's parents- Grandma and Grandpa.
Father's - Granny and Grandpa.
My children called both Grandpa's, Grandpa and both Grandma's , Grandma with their names attached as both sets had said they wanted to be called Grandpa and Grandma.
The same has happened with my grandchildren. Mr. Boris and I are Grandpa and Grandma but are diferentiated from the other Grandparents by our names.
The odd thing is that in both cases the 'other' set of Grandparents had traditionaly been called 'Nanna and Grandad'.



but hey....what does it matter if all are happy 1
As my Grandma always said
" you can call me what you like as long as you don't call me late for my dinner " boom boom !