Request #154

I’m looking for a YA mystery romance novel that I read in junior high in Canada, probably published in the late 1970s or early 1980s, possibly through Scholastic. I don’t remember the cover. The details in my mind are so vague: It was a female protagonist, 17 or 18, possibly first-person; I don’t recall her name. She was temporarily living in a house near a marsh/swamp/quicksand (no idea what country). She might have been there to take care of a senior man and the romance involves a great-nephew or grandson. It had a feminist bent, since she wanted to be referred to as “Ms” not “Miss”—but I believe she ended up engaged to the great-nephew or grandson at the end. Someone in the household had vanished years ago. A clue to the murderer’s identity had to do with a cape (or a rain poncho?); I think it was discovered in a knitting basket. The book cited lines from a Lewis Carroll poem: “‘You are old, Father William,’ the young man said…”