So I've decided to keep Whisper, again. When it comes down to it, I just really don't want to part with her. I can teach her to run barrels, even if she's not great at it, we can still have fun until I'm ready to move up. Her size is still bothering me a little though. She's only 3 years old, and I'm sure she will still grow a little more. But at 14.1hh and as petite as she is, I still feel huge on her.
So my question is, would a muscle building supplement help her to fill out, or is that not a good idea with such a young horse who still has growing to do? I don't know how these things work, and I want to make it as comfortable as possible for both of us. She's almost at her max weight carrying capability with just me, going by the 20% rule.
Any thoughts or suggestions?