Hi jackie, I agre with the earlier replies and emphasise that if you are not skilled in continence management, please do refer her to someone who is, there is a lot she will be able to do to help herself and yes people who do Pelvic floor exercises and they dont work, are usually doing the wrong action - pushing down not pulling up - or are doing too many or (more commonly ) far too few. also doing PF exs lying down is useless if the problem only occurs when she is doing exercises, the PF exercise programme needs to be tailored to the patient just like an exercise programme for any other muscle - graded resistance, increased reps, increased holding times etc.
Good luck, and if you havent done any WH & Continence stuff thus far, give it a go, its absolutely fascinating and consists of far more than just "the pelvic floor"!!