Ya know, I swear these little stinkers have their own little deals sometimes....just to make us post about them.
Marcel does this *out of the blue* sometimes too, and it freaks me out and confounds me to no end. Is he cold, hungry, low sugar, nervous, scared? Oftentimes, it seems none of the above. It'll sometimes come out of nowhere. Sometimes it'll be here and there for a few days in a row (like what you're seeing). At those times, I almost wonder if he's picking up on a smell in the neighborhood (something dead perhaps?) or a sound of an animal in distress. It's really weird and mysterious - and I always feel like a bad mother when I can't console him out of it, or figure it out - and then *poof*, it's gone as mysteriously as it appeared. Little poop.