My mom is searching for a book she read as a pre-teen about a girl named Max Moonpenny. I have searched and searched (and I even work in a library) but I can’t find anything about this book! She’s not sure if the title is Max Moonpenny or if it is something else. My mom grew up in the 1960s & ‘70s in Wisconsin, and a friend of hers also remembers the book and her niece was even named Max Moonpenny after the character from the novel. Unfortunately, the niece is prolific on the internet and clogging up my search results.

Any assistance would be greatly appreciated!