Alright this is going to get in-depth.
I'm the youngest grandchild on my dad's side of the family.
My dad's mother is Grandlady. Yes, we are southern, haha. It fits here though, she is a southern lady through and through. My dad's father was Papa, and his new wife was just her first name.
My mom's mother died before I was born, but my granddad (as we called him) re-married, and we called his new wife Grandma Jean. The rest of my family weirdly called my granddad "Beebop". I have no idea why. I refused as a kid,
I call my step-grandparents Oma and Opa since they're German.
My dad is called "Pop" by my nephews and nieces. Not sure how I feel about it yet...My step-mom is called Omi (since she's German) and HATES it. It's stuck now though....