For the past few mornings my dog Charlie has woke up yelping. I have never heard him make this sort of yelp before and it is very distressing as it sounds like he is in a lot of pain. I jump out the bed and as soon as I touch him he stops and goes back to sleep snoring away as usual. He sometimes has problems with his legs. He has to be carried up the stairs. On the last visit to the vet she said his heart is healthy for his age (he will be 10 this year) but he may have arthritis. His legs have seized up and became very stiff in the past, lasting around 5-10 minutes. I thought this may be what was happening during sleep and causing the yelping, but like I said as soon as I clap him he is fine, so therefore I don't think it's that? Any advice would be greatly appreciated!