Arthur is brilliantly litter-trained and has been since he was 10 weeks old (he is now over a year old).  However, two or three times in the last couple of months he has left little spots of pee behind.  Not enough for a full-on wee, just little bits.

His litter tray is still full of what it should be, and he eats and drinks normally.  Need I be concerned?

Just so this isn't all words, here is a pic taken tonight:







x-posted