My boyfriend and I took Sophie to the park to play the other day. We were having a great time running around and playing with her big red ball, when all of a sudden she ran off to the side and sat down, and when she got up she whimpered and started to limp. She was not putting pressure on her back right foot. She has been limping around for 2 days now. She lets you touch it and pull on it without crying. I looked to see if maybe there was something stuck in her paw pads, but I didn't find anything. This has happend once before where out of nowhere she started to limp. I watched it for a few days, and then I felt it was necessary to take her in. The vet couldn't say what it was. He gave her a cortisone shot and she was fine. So I guess my question is has anyone else had this kind of a problem, and, if so, what do you do and is it something that keeps on happening?