Parents are failing to teach their children how to get a good night’s sleep, according to a leading British psychologist. Tanya Byron said that youngsters get ‘a bad press’ for their ‘lack of manners, poor grades and terrible diet’. Writing in the British publication the Radio Times, Miss Byron, who is a TV broadcaster and Government adviser on children, said the reason for the difficulties was “a profound lack of sleep”. “This crisis is harming our children and young people, with two million suffering from sleep disorders in the UK.”, she said. “In young children – 65 per  cent of whom are significantly sleep-deprived – this can lead  to increased hyperactivity and other behavioural problems, as well as damaging their physical and mental development.” “Their problems generally stem from parents who are not teaching them good sleep behaviour, and are letting them stay up too late, sleep wherever they want and wake in the night for snacks and attention,” she added. She said Britain was “in the midst of an unspoken public health crisis due to escalating levels of sleep deprivation”. Miss Byron, who looks at sleep issues in Channel 4 show Bedtime Live, said many teenagers struggled to get six of the nine hours of sleep they need a night.  She added: “Teens blame work pressures and anxiety for keeping them awake, as well as their use of computers and mobiles late into the night.” “They are also struggling to fall asleep because the light that comes from screens delays the release of the sleep hormone melatonin, which is released in response to darkness.”