It was an interesting dinner discussion with A&M M. about family titles - what does the son-in-law, daughter-in-law and grandkids call you? The only experience Susan and I have in this category is what do we call our in-law parents and what instructions (if any) did we give our children on what to call their grandparents.
The variations are endless. The traditions are driven by past chains of ancestor titles. As an example, it was important for Susan that our young children call me "Papa" and her "Mama". As they grew up that evolved to Dad and Mom (and on occasion Father and Mother). Our children call my parents Grandma and Grandpa (without the surname Wisner) and for Susan's parents the titles are Popsie and Nonny (although I think it should be spelled Noni). Both Susan and I call each others parents by first name.
Generational spans create the challenge of addressing your elders. Only after years of being out of college was I comfortable addressing people eight years older than me by their first name. Consequently addressing Susan's parents by their first name took time to get comfortable with.
The available nicknames for Grandparents are always fun to hear - Grammy, Gamma, Mamey, Mimsy, Noni, Nana, Nanny ...... Gramps, Grampy, Pappy, PawPaw, Grandad, Poppa .......
My niece is expecting so Mom and Dad will become Great Grandparents soon. Hmmm....... I wonder about Great Grandparents titles.