Idalmina Petrie is the wife of The First Avery Petrie, and mother of Avery Petrie Jr Sr. And so she's Avery Petrie's not-grandmother. (Avery's REAL Grandmother also known as Jim Cornette's mother is unknown person. Although, Avery's real Grandgrandmother is Eva Braun.) She died on unknown year.
According to Youngest Avery, she was a "drug-addicted mental patient, who left Avery's father (It was obviously Avery Petrie Sr Jr, because Avery denies the existence of Jim Cornette as his father.) with a ton of debt.
This might be considered as another reason why Avery Petrie's parents divorced and caused a huge downfall in Avery's life.
- She is the only known feminine grandparent in this part of site alongside the above-mentioned Eva Braun and Fortan's grandma, who could survive an apocalypse.