My dad was funny, and liked being funny. He sent me letters every time I went to camp. I looked forward to the letters so much they were typically the only reason I would stop crying about having to go away to camp.
I sincerely apologize for his use of the term "gypsy," or the implication that the Romani people eat cats. Also "Jap Patrol."
I do not think Dad meant to disparage any ethnic group in a specifically hateful way. Instead, I would say that he liked to make fun of everyone.
I do not know if he dictated the letters to his secretary, or if she typed them up from his written notes. He was not actually affiliated with the Clayton Fire Department, but did work for the Ralston Purina Company.