The Crucial Role of Sleep in Your Baby’s Growth and Wellbeing

It’s common to hear phrases like “No one sleeps after having a baby” or “Babies just don’t sleep through the night.”These ideas have become so familiar that many parents begin to see exhaustion as an inevitable part of early parenthood.

While it’s true that babies wake for many reasons — and that caring for a little one can be demanding — it doesn’t mean sleep deprivation should be accepted as normal. When we understand just how essential sleep is for a baby’s health and development, it becomes clear that supporting better rest benefits not only the child, but the whole family.

Sleep plays a vital role in every stage of growth. A peaceful night’s rest supports emotional balance, physical recovery, and learning — all of which are especially important in the early years, when development happens at an astonishing pace.

According to the National Sleep Foundation, a leading American organisation specialising in sleep health, sleep is as fundamental as nutrition and hygiene. In addition to supporting intellectual development, it is during sleep that the body releases growth hormones — essential for healthy development.

Dr Ellen Balielo Manfrim, a neuropaediatrician, neurophysiologist, and director of the Integrar Clinic in São Paulo, Brazil, emphasises that during sleep, a child’s body and brain undergo critical processes such as growth, memory consolidation, hormonal regulation, and cellular repair. In other words, it is while a child sleeps that their body performs its most important restorative work.

Sleep also plays a key role in mental health, helping to reduce stress, improve concentration, and consolidate the information learned throughout the day — all of which enhance emotional balance and learning. Adequate sleep, both in quality and quantity, is therefore fundamental for a child’s healthy development.

Impact on mental health

Research continues to show just how strongly sleep affects emotional wellbeing.A study conducted at the University of Birmingham, England, found that poor sleep quality in childhood was associated with a higher risk of mental health issues in adolescence. Analysing data from around 14,000 children, the researchers discovered that inadequate sleep was linked to an increased likelihood of developing borderline personality disorder. Moreover, the study highlighted connections between disrupted sleep and the onset of depression, particularly around the age of ten.

Similarly, research from the University of Maryland in the United States revealed that children who do not sleep enough are more likely to develop psychological and behavioural difficulties than those who meet their age-appropriate sleep needs.

After two years of follow-up, the study showed that sleep-deprived children exhibited higher levels of impulsivity, stress, depression, anxiety, and aggressive behaviour. Their cognitive functions were also affected, impacting learning and decision-making abilities.

The Royal College of Paediatrics and Child Health underscores that good sleep is fundamental for children’s health, shaping their emotional wellbeing, growth, learning, and overall development. Disrupted or inadequate sleep, when frequent and persistent, is recognised by paediatric professionals more broadly as a contributing factor to issues such as irritability, reduced cognitive performance, behavioural problems, and diminished memory function.

It is therefore evident that a persistent lack of quality sleep in childhood can be profoundly harmful to mental health, with lasting effects that extend into adolescence and adulthood.

Impact on development

The first two years of life represent a period of intense brain growth and learning. In just the first year, a baby develops countless new skills — eating, playing, rolling, crawling, and communicating, among many others.

However, when a child doesn’t get the sleep they need — in both duration and quality — their behaviour reflects it. Like adults, tired children experience fatigue, but they may also show irritability, restlessness, difficulty concentrating, hyperactivity, and reduced engagement in activities.

Over time, chronic sleep deprivation can impair not only neuromotor development but also mental health, and it may even disrupt hormone production. This can contribute to issues such as obesity, reduced muscle development, and a weakened immune system.

How Much Sleep Do Children Need?

The number of hours a child needs varies with age. Based on extensive research, the National Sleep Foundation has created a helpful reference guide outlining the average sleep requirements for each developmental stage.

Newborns - 0 to 3 months	14 to 17 hours
Babies - 4 to 11 months	12 to 15 hours
Children - 1 to 2 years	11 to 14 hours
Children - 3 to 5 years	10 to 13 hours
Children - 6 to 13 years	9 to 11 hours
Adolescents - 14 to 17 years	8 to 10 hours

However, it’s not just about how long a child sleeps — the quality of sleep matters just as much.Ask yourself: Is my child sleeping peacefully? Is their sleep restorative and undisturbed?

Observing your child’s cues and establishing a consistent bedtime routine can make a world of difference. Every child is unique, and understanding how sleep influences their development — while respecting your family’s rhythm and reality — helps create the foundation for healthier, more restful sleep.

If you’d like to learn more about how to support your baby’s sleep, reach out to us today. Taking that first step can bring your family closer to the rest you all deserve.

If you’d like to understand more deeply what lies behind your baby’s changing sleep patterns — and how to support them through each phase — the Infant Sleep Academy is here to help. Our L.O.V.E. Method will guide your family with science, empathy and gentleness, helping you rediscover rest as it’s meant to be: natural, respectful and full of love.

By Mariana Friend

Infant Sleep Specialist, founder of the Infant Sleep Academy, and creator of the L.O.V.E. Method — a compassionate, science-based approach that honours each baby’s unique rhythm and nurtures rest through connection.