Not getting enough sleep can contribute to anxiety and other serious health issues like heart disease and obesity in schoolchildren, a leading sleep expert has warned.
Irish sleep consultant Lucy Wolfe, of Cork's Sleep Matters Clinic and author of The Baby Sleep Solution, claims sleep is more than a behavioural technique.
"It is not always the case that children outgrow their sleeping problems," she said.
"Continued broken sleep and not enough sleep could be a contributory factor to a compromised immune system, lack of concentration and anxiety.
"As many as 70pc of parents reporting struggles with their children's sleep have symptoms that go way beyond the typical duration.
"Most research has concentrated on the brain consequences of sleep loss - based on the belief that sleep is for the brain alone.
"There is now growing evidence that short-duration sleep results in metabolic changes that may contribute to the development of obesity, insulin resistance, diabetes and cardiovascular disease.
"According to a recent study, for each additional hour of sleep, the risk of a child becoming overweight or obese is lowered by an average 9pc."
The research showed children who slept least had a 92pc higher risk of being overweight or obese than good sleepers.
Ms Wolfe believes it is important that parents understand the biological necessity of good sleep.
"Lack of sleep in children, together with the overuse of electronic media, may lead to serious health and emotional implications," she said.
"Studies show sleep deprivation can acutely increase blood pressure and sympathetic nervous system activity. Prolonged short sleep duration could lead to hypertension."
The best-selling author added: "Children respond best if parents are consistent, so they know what is expected of them.
"Consistent sleep habits include bedtime routines, bed time and wake time. Remove TV, computer and video games from your child's bedroom.
"Allow your child to sleep-in, but no more than two to three hours beyond the usual wake time.
"Being overly emotional, having easily-hurt feelings and lacking patience are all signs of a lack of sleep.
"Also difficulty waking in the morning, having trouble concentrating or focusing when playing, taking excessive naps, hyperactivity, defiant or contrary behaviour."
Other signs to look out for are difficulty falling asleep (being overtired), falling asleep immediately (sleep should take about 20 minutes in a healthy sleeper), increased appetite, and being accident prone or clumsy.