My grandma slides on her lift chair and I'm always having to yank her around and I'm so afraid I'm going to hurt her. Her backs hurts as it is and when she slides down it puts all sorts of pressure on her back and she ends up screaming out in pain when sleeping. Does anyone have any ideas of things besides a sheet (I tried but it allows her to seriously slide out of the chair and I'm so afraid she's going to break something) that will allow me to move her easily but won't allow her to slide out of the chair? I'm alone and she out-weighs me by a bit so I can pull her around but it hurts my back and arms and isn't exactly pleasant for her. Thanks.