Clover GBS would have no impact on her fertility. Has it been confirmed she has GBS or something they suspect? You don't usually have a mild case and relapse later on although once you have had it once you can get it again apparently but its very uncommon. Usually at the onset of the illness deterioration is rapid and within 24hrs-48hrs the patient nearly always needs to be ventalated due to it compromising the respiratory system and not been able to breath for yourself. This acute stage usually lasts anywhere from a few days until a few weeks until you can breath on your own and further time to get use of the arms, legs etc. Then physio to gain use of them and muscle tone. The myelin (covering of the nerves) does repair itself and once it does people usually have full mobility again. Just takes time.