Experts said he was suffering from a severe behavioural disorder with psychopathic tendencies.

BBC: Dutch teenager convicted of Facebook murder

The advice also stresses the need to make sure that children take medicine for conditions such as attention deficit hyperactivity disorder or for behavioural problems on the trip.

BBC: NEWS | Health | Homesickness 'can be prevented'

It is believed that sleep deprivation may harm neurological development and can contribute to behavioural problems including attention deficit hyperactivity disorder (ADHD).

BBC: Children losing out on sleep

Glasgow University expert in infant mental health, Dr. Philip Wilson, said the problem of language delay amongst Scotland's two and a half year olds had to be tackled now, before associated behavioural problems like Attention Deficit Hyperactivity Disorder, set in, when they're older.

BBC: Finance Committee 3