The Berenstain Bears used to be the Berenstein Bears. LOTS of people remember it as being that way. I do also, to be honest. I had always thought that that was just the more natural way to spell that name, but I also figured that things aren't always as they "feel" right to spell, especially with names. I find myself triple-checking the name when I write about it.
But then? Adelaide Dupont left a comment on my blog about the Mandela Effect, so called because apparently plenty of people also remember Mandela dying in the 1980's. Thousands of people out there distinctly remember the BerenstEin Bears from their childhoods as well.
Another jump: because so many people remember things happening differently than we understand they did today, it's really just proof of parallel universes and these are remnant memories of some kind before things switched. Go ahead and google it - there are a lot of people talking of this. Wow.
Know what? I think we'll find with a bit more research that humans have some sort of logical thought process and sometimes get stuck in certain pathways. Mandela could have easily died in the 1980's and the Berenstains could easily spell their name differently and it wouldn't have been an unusual thing to have had happen. And then our thoughts travel that way but that's not how it really is. Perhaps human brains have "thought grooves" and we tend to think along a certain line.
There's my theory anyway.
Edited to add: I'm not alone. Russell Smith calls this difference between memory and reality Shrodinger's Nostalgia, whereby two distinctly different thoughts are perceived to be true at the same time.