My mother is American. Her parents met during ww2 in Brazil, where my grandfather was stationed. So maybe it was a lie that permeated those involved with the war at the time. I accused her of spreading fake news this morning after reading this and she couldn’t recall where she had heard it.

I just asked my wife, who is from Hong Kong, if she had heard this as a child and she said she had not. Her grandparents were really young during the war and Brits and Cantonese were pretty segregated until after ww2, so it might make sense that this didn’t reach her family.