Expert Opinion

Child Habits

Why does my child suck their thumb or pick at their nails?

Do you have a little thumb-sucker or nose-picker at home? Many children have habits that typically started as a comforting or regulating practice, but have then stuck around despite your child since learning other ways to manage the situation. Some of the most common habits in children are nail biting, hair twirling, nose picking and thumb sucking.

Habits are in essence, a pattern of repeated behaviour that seems to be occurring almost unconsciously – the child isn’t aware they’re doing it. And while we’re not 100% sure what actually causes habits, we do know that they’re learned behaviours that provide some kind of ‘pay off’ for the child.

In my experience, habits often form as a way for a child to soothe themselves. A way to self-regulate if they’re feeling bored, anxious, unsettled etc. I often notice that these types of habits tend to increase at times of stress for children. Yet some habits have a strong familial component – like nail biting, so if you’re a nail biter your child may have picked this habit up from you.

Most habits are a part of normal childhood development and will go away by themselves. Children with certain disabilities, autism and other additional needs can have more pronounced habits than other children, or their habits might last longer – or there may simply be more habits.

You might need to step in and help your child break the habit if it is getting in the way of their everyday activities, is causing damage in some way, or is embarrassing for them. BUT if you think the anxiety might be underlying your child’s habits – make sure you address it so you don’t end up playing a game of ‘whack-a-mole’ by replacing old habits with new habits.

Should I be worried about habits like chewing on objects or teeth grinding?

While mouthing and chewing on objects can be quite common in babies and infants, oral sensory-seeking behaviours that extend beyond ‘exploratory’ function during the early toddler years can be a sign of oral hyposensitivity. This is when someone has less awareness in their mouth and has a high threshold for oral input. Basically, the child needs more oral input, so the clever little mites problem-solve this for themselves by seeking orally stimulating activities that give them lots of ‘feedback’ in their mouth. Enter excessive chewing on their shirts and other items. In these instances, I highly recommend seeing an Occupational Therapist who can provide some alternative strategies for your child to have these sensory needs met.

Despite the somewhat jarring sound of it, teeth grinding itself is usually no cause for alarm because most children outgrow it by the time they’ve started school. It’s said that there’s no clear cause for this behaviour however stress has been suggested as a contributing factor. I can recall counselling sessions with children who started grinding their teeth when things became more challenging – always a good little cue for me to wind things back a bit! I have also found that teeth grinding can be a common form of self-stimulation in children with autism – it might help to regulate them, particularly in more stressful situations.

The challenge with teeth grinding is that it can cause teeth to wear down as well as contribute to jaw pain, headaches and earaches. A dentist is a great place to start if you’re worried about this habit in your child, as well as looking for any underlying stress or anxiety.

How do I help my child break these habits?

A great place to start is to work out WHY the behaviour is occurring – or continuing. What’s the ‘pay-off’ for your child?

  • is it because it feels nice?
  • Is it associated with a particular situation – like thumb sucking when tired
  • Is it to get a reaction from you?
  • Is it simply a ‘leftover’ habit from when they were younger

You can then think about teaching replacement behaviours that might have the same ‘pay-off’ but at a lesser ‘cost’. This could include offering a thumb sucker as an alternative soothing activity. In addition to this, encourage competing behaviours which make it impossible for your child to engage in the habit – because they can’t possibly do both behaviours at once. For instance, if your child picks at their nails while watching TV, by giving them a toy to hold on to or a fidget toy to ‘pick at’, they might slowly decrease the amount of nail picking. You can’t pick your nails while playing with a toy.

As the parent, stay calm about the behaviour and try to explain a rationale as to why it would be good to stop. For instance “putting your hands in your mouth can give you germs and make you sick” or “sucking your thumb is not good for your teeth”. However avoid making a big deal out of it, and certainly don’t use punishment.

Using rewards however can be helpful for behaviour change with habits, so you might praise your child or give a sticker for situations where they are using a replacement behaviour or refraining from engaging in the habit.

Ultimately, to break a habit you’ll need motivation from your child and a lot of patience – habits can be present for a long time so they can take a long time to break!

What is a tic and is it a habit?

While many people might think a tic is a habit, it is actually a repetitive involuntary muscle movement (motor tic) or sound (phonic tic) that your child may not even be aware they’re doing, and have no control over. Just in case you were wondering if a child has both the motor tic and the phonic tic presenting together for longer than a year, we consider a diagnosis of Tourette Disorder. Tics most commonly start around early primary school age and, in short, bouts called transient tics, can affect about one in eight children. When a tic persists for longer than a year it can be a sign of Chronic Tic Disorder which affects about one per cent of children – half of whom will outgrow the tic by adulthood.

Tics are more common in children who have another family member also experiencing tics and often children who present with tics also have other conditions such as ADHD, learning difficulties, mood problems or Obsessive Compulsive Disorder.

Tics tend to increase when the child is experiencing big feelings, like stress or excitement – even tiredness. And they can change over time – often as one tic stops, a new one is formed.

If you’re worried your child might have a tic, see your paediatrician to rule out any medical conditions and to discuss ongoing management which generally involves active ignoring of the tic because unfortunately, drawing attention to the tic increases its occurrence (which can then increase the child’s stress or embarrassment, which then increases the tic even more…). Your medical professional might also suggest treatment options that involve implementing lifestyle changes to manage your child’s emotional regulation.

About the author

Amanda Abel is a paediatric psychologist, mum, and founder of Northern Centre for Child Development (NCCD) and Hawthorn Centre for Child Development (HCCD) – multidisciplinary paediatric practices in Melbourne. Working directly and indirectly with hundreds of clients each year, Amanda’s mission is for every child to achieve their best outcomes by equipping families and educators with the tools they need to help kids thrive.
Amanda draws on her own experiences of being a parent along with her extensive training and well-honed skill set to get families thriving. Having worked with families for almost two decades, as a psychologist for the past 11 years in a variety of settings, and a valued board member of the Autism Behavioural Intervention Association, Amanda loves building the confidence of the adults in the lives of children so that they can connect meaningfully, help them reach their full potential, and live a life that reflects their values.
Often appearing on Channel 7 and 9 News and regularly featuring in print media, Amanda is on a mission to make the world better for kids through her clinical work, consulting to some of the biggest global toy manufacturers and educating the digital media industry about making the internet safer for kids.