Sleep. Many children make a sport out of resisting it, reaching Olympic levels of prowess in bedtime shenanigans.
And while night waking is a part of human sleep, requiring adult attention on every night wake is not only tiring for parents but may also be indicative of children’s overall ability to self-regulate.
Self-regulation is an important skill gained during the early years, which helps children to maintain and focus attention and also control their own emotions and behaviours.
In the end, though, does it really matter if children aren’t sleeping well?
Longer-term effects of poor sleep
We analysed data for 3,000 children participating in a larger longitudinal study, with data collected every two years from birth to nine years. Our analysis found that if bedtime behaviours persist beyond infancy, this could have implications for children’s emotional and attentional development two years later, beginning from the first year, and up to the age of nine.
The research focused on behavioural sleep problems such as bedtime resistance, persistent night waking and trouble falling asleep and resettling independently. These are distinct from medical sleep problems, such as sleep apnoea, which is difficulty with breathing during sleep, and from the length of time that a child sleeps.
Infants naturally need a lot of support at bedtime and during the night. For most children (70%) such sleep behaviours steadily improved.
At five years old, these children showed no regular ongoing sleep problems. They were independently settling themselves at bedtime and at night waking (unless sick or at other upsetting times).
For the remaining 30% of children, these behavioural sleep problems escalated from birth to five years. These children required more and more adult support around sleep across this time period.
In the classroom at six years of age, teachers of this group of children rated them as more hyperactive, emotionally unsettled and disorganised, and as having poorer social skills. This is likely due to sleep problems influencing brain development over time in a way not conducive to developing self-regulation skills.
Children with sleep problems may have over-reactive emotional responses to events during the day and be preoccupied with trying to regulate their emotional system. This limits their opportunity to focus and benefit from activities that build attentional regulation.
Of course, not all five-year-old children with sleep problems will struggle to adjust to school, but for those who do, sleep might be an important target for change.
The research detected differences in the extent to which parents reported their child had a moderate or severe sleep problem for children later diagnosed with clinical symptoms of Attentional Deficit Hyperactivity Disorder (ADHD).
From as early as two years old, children who were later diagnosed with ADHD had significantly higher levels of parent-reported sleep problems, including bedtime resistance and night waking, than children without ADHD.
While prevalence in sleep problems for the non-ADHD group decreased substantially from birth to seven years, for the ADHD group rates of sleep problems remained more stable across this time (around 20% of these children continued to have sleep problems up to age seven).
Whether or not toddler sleep problems were an early sign of underlying neurological differences in children with ADHD or contributed to a mutually exacerbating cycle of poorer attentional behaviours over time is yet to be fully understood.
Programs that support parents to manage bedtime with warm and firm routines and rituals and to use behavioural techniques to gradually withdraw adult support for falling and staying asleep are largely effective.
They not only directly improve sleep behaviours but also improve children’s daytime behaviour and attention in both the general population and children with ADHD.
There is no strong evidence that such techniques cause long-term emotional harm – and the immediate benefits for child development, family functioning and parental wellbeing are considered to outweigh any small chance of risk.
Techniques differ according to a child’s age and can be adjusted to accommodate parents’ individual comfort levels with leaving their child alone to settle.
Ultimately, parents should have the final decision about the approach they take, as consistency and commitment are key to all approaches.
The ways that children’s sleep is managed varies greatly from house to house and across cultures. If parents are concerned about the way children are adjusting to school, developing social relationships, coping with their own emotions and managing their attention, then sleep behaviours is a conversation to have and consider addressing.
The short-term pain of sleep training in early childhood is likely to reap long-term gain for children and families.
Kate E. Williams does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.