If you have a child that wakes every morning looking like they still need a decent night's sleep, it can be frustrating and concerning. Even after creating an ideal sleep routine and allowing children to settle naturally, some children still struggle to get a consistent night's rest.
Scientists have just diagnosed a new condition which explains around 7 per cent of children's sleep problems: Restless Sleep Disorder (RSD). It affects children aged six to 18, and although these children may feel like they've slept all night, it's their quality of sleep that is affected.
Children with RSD toss and turn more than others and, during their waking hours, often have a tough time focusing, resulting in emotional and behavioural challenges.
The researchers who recently defined RSD say their findings are an exciting development, providing a "why" for families who have children struggling to get high-quality sleep.
"Before this, we didn't have the tools — a standard of diagnosis — to say, 'Oh yes, your child has restless sleep disorder,'" Dr Lourdes DelRosso, of the University of Washington School of Medicine and Seattle Children's Hospital, told HuffPost.
There wasn't really anything doctors could do for those children previously, DelRosso said, and "that's what makes this very important," she said.
Brisbane mum Stella* says her nine-year-old daughter Penny* has been a terrible sleeper for a couple of years now, and is often grumpy or distracted during the day. Stella is currently talking to Penny's doctor about an RSD diagnosis, but she says it's tough because the condition is so new.
"We've been at our wits' end with her," she says. "She seemed to be getting enough sleep, but she was always complaining about feeling tired. She has a short fuse these days and it's been hard for the whole family to deal with it.
"But it wasn't until my husband slept with her one night that we realised how violently she thrashes around in her sleep. Our other children might kick around a little bit, but Penny actually gave my husband a fat lip by punching him in her sleep!"
Stella says Penny's school work has suffered too.
"Penny's report card has taken a massive dive over the past three semesters," she says. "If she doesn't get a decent night's sleep soon, I don't know what we'll do."
Not getting enough quality sleep can be damaging, says Dr Verena Senn, Head of Sleep Research at Emma – The Sleep Company.
"Sleep allows us to consolidate new memories, as well as rank and classify new experiences," she says. "We also need sleep to acquire new skills. For children, sleep is incredibly important as they are constantly learning and developing.
"Interestingly, the sleep architecture of children is different from adults. They have more 'dream sleep'. Researchers assume higher brain activity during this phase of sleep is vital for brain maturation helping children to build new connections between neurons. Longer sleep duration in children is consequently associated with better emotional regulation, better academic achievement and better health."
If you're concerned about the amount of sleep your child is getting, Dr Senn recommends first ensuring you have a good sleep routine, including a regular bedtime.
"Everybody has an inner clock ticking that loves regularity, and a child's clock is especially sensitive to change," she says. "Large differences between bedtimes confuses your child's inner clock and can lead to problems falling asleep as well as decreased sleep quality."
But if you suspect your child may have RSD and sleep has been an issue for your child over a long period of time, Dr Senn says it's best to talk to your doctor.
"This can either help reassure you that your child's sleep may be perfectly normal, or will be able to support you if there is an underlying issue," she says.
The treatment for RSD is a simple iron supplement, with researchers finding a strong link between the condition and low levels of ferritin, a blood protein that stores iron.
Dr Venn warns against parents self-diagnosing small sleep disturbances though, and says it's important to understand that children's sleep differs vastly from adult sleep.
"It is normal that sleep is more fragmented, for example, especially in the first years," she says. "It is good to pay attention, but it is also important to not overinterpret temporary sleep issues.
"Sometimes, kids will have trouble sleeping, and that is completely normal. If parents stress out, that can directly negatively impact the sleep of their child. While it is frustrating, staying calm and patient may be the simplest solution to helping solve your child's sleep issues."