I can't find a reference anywhere, but I remember reading that when their child was born they couldn't process a birth certificate with the name containing a slash, so it was changed to a dash for the kid.
Reading the article, I'd guess the introduction of the slash was introduced because the actual letter (Ꝃ) wasn't available on earlier technology like a typewriter. Funny that the "fix" caused problems with the next generation of tech.
I can't find a reference anywhere, but I remember reading that when their child was born they couldn't process a birth certificate with the name containing a slash, so it was changed to a dash for the kid.