Leading foal, gone wrong

hello, I'm back with another one of these, talking about not so great aspects of my barn.

so what problem did I notice today, well let me tell you.

my barn is notorious for telling younger students to do things that is outside of their capacity, this is mainly outside of the lesson time. They have two tall horses, one tall mare and one foal on the size of a large pony. They are private owned by one of the owners and the filly is about 5 months so she can be weaned, but isn't. She is not leading broke either and can't stay calm if she is one meter away from mom.

so the barn owner told my sister (12) and friend (11) to lead these horses inside. My sister's friend led the mom and my sister was supposed to lead the filly. My sister asked if I could bring her outside and she could take over, but her friend didn't stop after going outside so we had to change plans. Apparently she couldn't stop the mare, who wanted to go inside and when I tried to slow down the filly she reared and bucked, she started cantering. I just had to run with her and try to slow her, she stepped on my shoe, but it did nothing to me. In general it was just scary, and I don't want to see my sister handling that now. Seeing as she is not that sure around all horses and don't have the strength to hold them back.

in my opinion the filly should be weaned as they are standing at night in a way to small stall for two horses, if not she would freak out. At least she should be trained to go nicely, I get foals are just kids, but this is how it is every time. If they don't want to train her that well they should stop telling children to do it and setting both the human and horse in danger.