Not much is known about his life or the specific conditions that led to his death, but according Meemaw in "Mitch's Son and the Unconditional Approval of a Government Agency" he died of complications related to surgery to remove something from inside him about nine months before his death. According to her, he "went to the doctor, and they found something. Two days later he was in surgery, and nine months later he was dead". This incident that was seen by Meemaw as leading to his death made her weary of doctors for several years afterwards.
He passed away in 1985 when Sheldon was five years old. Sheldon missed him and wanted him back and asked Santa to bring him back, but it didn't happen and this soured Sheldon so much that he hated Christmas altogether.
He was the only member of Sheldon's family who encouraged him to pursue science and in "The Meemaw Materialization", Meemaw says that he was a stubborn and egotistical man and there were days that she wanted to fill his pockets with corn and toss him in the pigpen, but she stood by him and made him into a better man, as revealed by Sheldon.
As a result of Pop-Pop's ego and narcissism, Sheldon seems to have picked up those traits, proving that he respects Pop-Pop to the point that he takes after him.
- Pop-Pop had a failed attempt at taxidermy as a hobby. His only successful work was a stuffed raccoon that Meemaw sold at a garage sale (with help from Missy) in the Young Sheldon episode Carbon Dating and a Stuffed Raccoon.
- Meemaw was talking to him in his tombstone in the episode Contracts, Rules and a Little Bit of Pig Brains.
- He is similar to Sheldon Cooper. He doesn't have Sheldon's super intelligence. But he does have rude and arrogant behavior.