Three year old filly is rather precious of her personal space and generally makes ugly faces at the 13 year old mare next to her. Occasionally, she body slams the wall with her hip or shoulder, which is taking its toll on the wall, as well as the auto-waterer that is installed on that wall. 13 year old ignores three year old.
There is no option to move three or 13 year old to a different stall. Stalls have bars along all upper interior walls, but are solid below.
I was thinking of attaching a thick, PVC plastic pipe, snug to the wall, at hip/shoulder height, hoping the bulge in the wall might be uncomfortable enough to keep her from continuing this behavior.
Comments or better ideas?