My 5 month old filly has a hard bump on her hind fetlock She's not lame at all, I just noticed it today when I was brushing her. I did some google-ing to try to figure out what it is and is sounds like an osselet. She goes out to pasture every morning with mamma and a retired qh gelding baby-sitter, and comes in every night. Yes she does run around like a maniac when she's feeling frisky, but no more than any other baby. This really bothers me that she could have already injured herself. It doesn't seem to be bothering her any but i just dont like the look of it, big nickel sized calcified lump in her leg. Is there anything I can do to make it go away???