:help: I have been riding my horse in her dream treeless for about 8ish months now, at first I thought it was good but after she got a bad back (been sorted by physio) I rode her again last night after a week off and the saddle seemed to be slipping side to side even though the girth was on tight. My horse used to be a bit rounder but now shes slimmed down the saddle seems too big for her? she is an id x tb, I think ive only just noticed as I have been riding my loan horse in his treed saddle and have noticed the difference between the two. Last night my horse was cantering on the right leg (something she has been really struggling with) and seemed happier to go forward so i havent got a clue as to whether the saddle has caused her sore back. Any ideas as to what i can do to stop the side to side slippage? she is wearing the dream pad recommended for this saddle.