I wouldn’t bother. It’s rose tinted specs at work. Girls on the horse yard bully each other just like they do in every other arena. Source: I had a horse when I was a teenager.
The OP was painting an incomplete picture, the complete horse based solution to bullying involves plate mail and polearms.
So they can push the kid over and it ends up stuck lying on its back like a turtle?
I’m afraid this is also a case of ochre-tinted helm — girls will bully each other even if their liege lord fully equips them.
Really? It seems obviously complete nonsense to me.