I hope Kat’s OK too... I’m a little worried if he went away for the weekend, what happened with her. His farm sitter is good, very skilled if she got worse, but still... I hope she didn’t end up with an abscess or something that needed attention.
I’m wondering if maybe she has the beginnings of navicular where she is sound for light riding, etc. but can’t handle circles like lunging without lameness. Or possibly arthritis. My first bet though would be navicular. If that’s the case she should be fine for a child’s light riding and trails, just not hard pounding work or lunging.