Yesterday was the first time the two had to stay at home alone for 5 hours. Kind of a gamble - not sure if Harley ever was alone for that long or if he will get along with Fitz.
Preparations included a new doggy gate to keep them from doing strange things in the living room, a new bean bag so that each of them has his own cushion, setting up toys, water bowls, etc in the hallway, laying out puppy pads and then just hope for the best.
Iris left the flat around lunchtime and came back in the afternoon. He seemed to be fine - obviously happy that she was back but not overly excited and no sign of distress.
But: There was a puddle on the floor. And Fitz was lying in it. Now we know that Fitz is slightly incontinent - he dribbles a bit when he is asleep for several hours - and he does wear a nappy when he is alone. But he normally does not leave puddles - and he was not wearing the nappy.
My theory: Harley was responsible for the puddle. To cover his tracks he then removed Fitzi's nappy (he is quite curious about it anyway and keeps tugging at it). Fitz then walked over to have a sniff, slipped and could not get up again due to his bad legs and the slippery floor.
The next time they are alone I will hook up a webcam to spy on them