i i have 3 horses my newest one purchased 4 wks ago. she was broken at 3 then left last yr and brought into work in april 00 ridden on a loose rein. i am having lessons on her but sometimes she backs up and i feel like she may go up she didnt i growled at her gave her rein then pushed her on. a friend rode her at the wekend - short hack then in field after a while horse napped leaped bucked then did it again then stopped reared and fell over. after we caught her friendot back on horse was okay but i am worried she might do this again. i had a leson thenext day and she was okay since then 2 short hacks. she rides out with other horse at the moment. anglo arab 16 hh quite build up. instructor was surprised as she classes me and the horse as quite laid back. friend is very confident rider not heavy handed i dont want this to happen again any help please.