Unfortunately, I never really had much of a relationship with any of my grandparents.
Both of my dad's parents were dead by the time I came along, and as for my mom's parents, they're a different story. I only met her biological father once, but as I understand it, he was extremely abusive and possessive, so she and her mom basically fled from him when she was still a kid. Otherwise, her stepdad/adoptive father was the grandfather I knew, he was my papaw, but admittedly, I didn't know him for very long . . . by the time I was eight-years-old, and after he had a car accident, he gradually slipped deeper and deeper into Alzheimer's, so he spent his last several years of his life in one nursing home after another, and I hardly ever saw him except for certain occasions, and even then, his quality of life deteriorated until he passed away on April Fool's Day in 2005 - I couldn't even go to the funeral or burial service, because my dad and I were both sick with the flu.
As for my nana (my mom's mom) . . . she was always incredibly distant, and I barely had a relationship with her . . . she certainly didn't fit the typical grandmotherly role of a sweet little old lady with a penchant for pinching cheeks and baking cookies - if I ever had to stay with her, she basically just let the TV babysit while she did her own thing. Likewise, she succumbed to dementia a few years ago and also passed away . . . I really hate to say this, but honestly, I felt no sense of loss when she passed, and I don't believe my mom did either.