The cause of KLS is unknown although it does appear that the onset of the condition coincides in most cases with a cold or infection and that this affects the part of the brain that regulates sleep. In the case of Louisa, the prolonged sleeps began in 2008 when she was recovering from a bout of flu.
Although highly debilitating when it occurs, sufferers of KLS generally average six months between bouts, during which time their sleep patterns are perfectly normal.
However, the good news for Louisa is that in the vast majority of cases, the syndrome disappears in teenage sufferers by the time they reach their twenties.
Click here for more information on KLS.