Name: Grandpa Fitzgerald
Other Names: Dr. Fitzgerald
First Appearance: Painkiller Jane (vol. 2) #2 (June 2006): "The Dead of Winter, Part Two"
Number of Appearances: 2
Enemy of: Painkiller Jane
Family/Relative: Ada Fitzgerald (wife)
Tom Fitzgerald's parents were members of the Nazi Party. His father was a doctor in a Nazi concentration camp. At the camp, Tom's father tortured, raped and killed young girls. Tom continued doing this, and his son - Johnny Fitzgerald - was the third generation of Fitzgeralds who did this.
All of them died at the hands of the vigilante Painkiller Jane.
"Fitzgerald" is not this doctor's real name. At the end of World War II, the Nazi doctor and his wife Ada knew trouble was coming from them as Allied forces overcame the Nazis. Ada killed the real Fitzgerald family. She and her family stole their identities and moved to America.
Suggested links for further research about this character and the character's religious affiliation: