Clowns can help children recover from illness.
Scientists have found that youngsters seriously unwell in hospital with pneumonia got better faster when they were visited by a face-painted entertainer.
Clown visits also cut the amount of time that the children needed to be on intravenous antibiotics during their illness.
The team followed 51 kids between the ages of two and 18 who had been hospitalised with pneumonia and separated them into groups - one of whom got visits from a clown and another that didn't.
Experts found that the group who were visited by a medical clown had a shorter hospital stay - an average of 43.5 hours compared to 70 hours for the other children - and think that a visit from an entertainer alleviates stress and anxiety in poorly youngsters.
Dr. Karin Yaacoby-Bianu, of the Carmel Medical Centre in Israel, said: "Laughter and humour may have direct physiological benefits by lowering respiratory and heart rates, reducing air trapping, modulating hormones and enhancing the immune function."