Nun's Knees

During one of my physio sessions at the new old people's home in Ibiza I was told that I have two 'nun's knees' - that's Housemaid's Knee in English. Using my new housemaid powers only yesterday, I spotted that there were one or two cat hairs on the living room carpet. It was only on closer inspection that I remembered we don't have a carpet in the living room.