Double bonk: Walking through walls

We’ve all seen where sims will once in a while walk through seemingly solid sim objects.  There’s one location in France where adventuring sims have tended to walk through one wall more than any other.  It’s a secret door in the Celtic ruins quest.  Here’s one sim that I was playing last month at that door…

And here’s a different sim at the same secret door earlier last summer…

There’s something not quite right with that door.