Nancy Drew and the Fight to Remember. That manuscript likely never got published.

"It was true. And she died. Obviously. And her name wasn't 'Mrs. Wizard.' It was Flagg. The same as mine. Mrs. Randall Flagg, née Nadine Cross. And she fell to her death from a very, very high rooftop while pregnant with our child. By that point, she was really quite mentally unstable. Are you happy now?"