United by a Common Language over What Was Lost

From the Boston Globe, Anna Mundow's book section interview with British Midlands novelist Catherine O'Flynn:

Q. The opening of your novel [What Was Lost] recalled for me the Enid Blyton adventures I read as a child. Does that make sense?

A. I think so because I was thinking back to my own childhood as I wrote this. I read Enid Blyton, of course, and things like "Alfred Hitchcock's Three Investigators." I also had the kind of books that Kate loves - "Clues and Suspects," "Fakes and Forgery" - which I took incredibly seriously. Being a detective is part of most childhoods, I think, because children spend a lot of time watching.

Q. We see the world initially through Kate's eyes. Why did that perspective appeal to you?

A. There's a lot to write about regarding what is lost between childhood and adulthood. I also found it almost embarrassingly easy to write in the voice of a 10-year-old. But it was important that she be real and vivid, not just a victim or a symbol of innocence. So I thought a lot about Kate; how seriously she takes things, how she doesn't see the humor in certain situations. . . . She's far more conscientious and professional than I was as a child detective.
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Q. Did you make changes for the American edition? You use "mom," for instance, not "mum."

A. It's funny you noticed that because it's actually Birmingham speech. We say "mom," and I didn't realize that wasn't universal in England until the book came out. Actually if you look it up in Wikipedia it says "used in America or in the British Midlands."

Actually, you have to look up "mother," and as of tonight it says mom and mommy are current "in most of North America (especially the U.S.). It is used widely in the West Midlands, in the UK." Mom appears to come from shortening mamma and momma, and its written existence is a little more than a century old while mum goes back seven more decades.