Hi everyone, Yesterday one of my yearlings got a swollen knee. It feels soft and fluid filled not hard at all. It is swollen on the front of the knee right under the rubbed area. It is about the size of a slightly flattened golf ball. He is in no pain. Running playing and head butting. My first thought was a bee sting or spider bite. I gave him children's benedryl and several asprin. No change. Any thoughts?