My father’s neighbor has always been “Ms Waldi” to me. 10 years after my mom and I moved out from his house, my dad told me when I was visiting that that’s not her real name.
That lady used to have a dachshund. “Waldi” is a common German name for them (or dogs in general), so my mom used to call her that. My dad copied my mom and I my dad. I still don’t know that woman’s real name.
Oh, and my dad’s new one also calls her by that name.