How to Support Siblings When a Brother or Sister Has ADHD or Autism
When one child is being assessed or diagnosed, it's natural for almost all of your attention to flow towards them. The appointments, the worry, the late-night Googling, the school meetings...it all adds up. But there's often another child quietly watching it all unfold: the brother or sister.
At Bay Paediatrics, we work with families across Tauranga and the Bay of Plenty every week, and one of the most common things parents tell us (usually with a flicker of guilt) is:
"I'm worried I'm not giving my other kids enough."
If that's you, you’re not a bad parent. You’re a dialled-in parent who’s attuned to your child’s needs. And noticing is the first and most important step in supporting siblings well.
This guide walks through what siblings of neurodivergent children often feel, why it happens, and the practical, evidence-based things you can do at home to help every child in your family feel seen.
For many families, this journey begins by noticing the signs of autism or ADHD in one child (such as differences in communication, focus, sensory needs, or behaviour) and then seeking a diagnosis to understand them. In New Zealand, getting clarity through an autism or ADHD diagnosis often settles the whole household, because everyone finally has a name for what they've been navigating. Whether you're at the noticing stage, waiting for an assessment, or supporting a child who's recently been diagnosed, the strategies below apply to every sibling in your family.
Why Siblings Need Support Too
Autism and ADHD don't only affect the child who has them…they shape the whole family. Siblings of neurodivergent children frequently carry a complicated mix of emotions: love and pride alongside frustration, jealousy, embarrassment, or guilt for feeling any of those things at all.
Some of the most common experiences include:Feeling overlooked. When one child needs more time, structure, and supervision, siblings can quietly conclude that their needs come second.
Taking on a caring role. Older siblings in particular may step into a "helper" or "third parent" role, which can feel like a heavy load for a child.
Embarrassment in public. A sibling's meltdown, stimming, or impulsive behaviour can be hard to navigate around friends or in busy places.
Pressure to be "the easy one." Many siblings unconsciously decide to cause no trouble, suppressing their own needs to avoid adding to the family's stress.
Confusion. Without clear, age-appropriate explanations, children fill in the gaps themselves…often with versions that are scarier or more self-blaming than the truth.
None of these feelings means your child is struggling or that you've done something wrong. They're a normal response to growing up in a busy, loving, neurodiverse household. The goal isn't to eliminate these feelings, it's to make sure your child knows they're allowed to have them, and that you're paying attention.
Eight practical ways to support siblings at home
1. Give them honest, age-appropriate explanations
Children cope far better with what they understand. Rather than leaving a sibling to guess why their brother gets "special treatment," explain the difference in language they can hold onto. For a young child, something as simple as "Beau’s brain works a bit differently from yours and mine..that's why he needs extra help with some things" can dissolve a lot of resentment and self-blame.
Books, short videos, and simple analogies all help. The key is to keep the door open: this is a conversation you return to as they grow, not a one-off talk.
2. Redefine fairness as "what each person needs"
Fair doesn't mean identical. One of the most useful things you can teach all your children is that fairness means everyone getting what they need . This will look different for each of them. A child with ADHD might need a visual routine and more reminders; a sibling might need twenty uninterrupted minutes with you at bedtime. Naming this openly helps siblings stop keeping score and feel that their needs are equally valid.
3. Protect one-on-one time
This is the single most protective thing you can do. Even ten or fifteen minutes of regular, predictable, undivided attention (and doing something they choose) tells a sibling in the clearest possible terms that they matter just as much. It doesn't need to be expensive or elaborate. Consistency matters more than grandeur.
4. Let them have their own life
Siblings need the freedom to pursue their own friendships, hobbies, and interests without always having to accommodate their brother or sister. Guard their birthday parties, their sports, their sleepovers. Being a sibling to a neurodivergent child should never mean shrinking their own world to fit.
5. Welcome the hard feelings
Children take their emotional cues from you. When you can say "It's okay to feel angry when your sister breaks your things. I'd feel angry too," you give them permission to be honest rather than bottling things up. Talking openly about your own feelings (including the difficult ones) models that no one in the family has to cope alone.
It also helps to arm them with a few simple things to say when peers ask awkward questions, and to make clear they never have to explain or defend their sibling if they don't want to.
6. Keep caring responsibilities in check
It's healthy for siblings to help out because it builds connection and confidence. But keep an eye on how much they're carrying. A sibling should be a child first and a helper second. Make sure caring tasks are shared across the whole family and that no one child is quietly absorbing an adult-sized role.
7. Connect them with other siblings
Sometimes the most powerful thing is simply meeting another child who gets it. Sibling support groups and young carers' services let children realise they're not the only one navigating this, which can be enormously reassuring. In New Zealand, organisations like Parent 2 Parent run sibling support programmes nationwide, and ADHD New Zealandoffers community connection for whānau.
8. Watch for when to seek extra help
Ups and downs are normal. But if a sibling isn't bouncing back (e.g if low mood, anxiety, withdrawal, or anger starts to affect their friendships, schoolwork, or sleep over time) it's worth seeking support. A school counsellor, GP, or a family therapist with good knowledge of neurodiversity can all help. Trust your instincts; you know your child best.
The hidden strengths siblings often develop
It's important to hold a balanced view. Alongside the challenges, growing up with a neurodivergent brother or sister can build remarkable qualities: deep empathy, patience, advocacy, emotional maturity, and an instinctive acceptance of difference that many adults never reach. Many siblings look back on this experience as something that shaped them profoundly for the better. Recognising both the difficulties and the strengths is part of supporting them well.
Looking at the whole family
When one child is assessed for autism or ADHD, it often shines a light on the wider family system. It's not unusual to realise that a sibling, or even a parent, is neurodivergent too, sometimes without ever having had a name for it. Stepping back to view your family through this wider lens can make everyone's behaviour easier to understand and respond to with compassion.
This is exactly why our ADHD and Autism assessments at Bay Paediatrics are designed to support the whole family, not just the child in the chair. Understanding your child's neurodevelopmental profile clearly is the foundation that helps every member of the household thrive.
How Bay Paediatrics can help
If you're navigating a diagnosis (or wondering whether to seek one)getting clear answers is often the thing that settles the whole household. With public assessment waitlists in New Zealand stretching to 12–24 months or longer, many families choose a private assessment to access answers and support sooner. Our specialist team offers:
Child ADHD assessment - ‘ADHD Illuminate’ is the leading paediatrician- and psychiatrist-led ADHD assessment and diagnosis for children in New Zealand.
Child Autism assessment - ‘Autism Horizon’ is the gold-standard autism (takiwātanga) assessment using MIGDAS-2, delivered by experienced clinicians.
Combined neurodevelopmental assessment - The ‘NeuroAtlas’ ADHD & Autism assessment is the most comprehensive child neurodevelopmental assessment in the country. This is for families who aren't sure which path fits, or where more than one profile may be present.
Our approach is neuro-affirming and strengths-based, delivered by expert developmental paediatricians and a child & adolescent psychiatrist who understand how autism and ADHD present in real children…including the subtler presentations that are easy to miss…
…And we specialise in helping those families where ‘the teacher thinks everything is fine’. But the parents know everything is BUT ‘fine’.
As Aotearoa’s leading neurodevelopmental clinic and home of the New Zealand Neurodiversity Centre of Excellence, Bay Paediatrics supports whānau across the Bay of Plenty and nationwide with clarity, warmth, and clinical expertise.
If you'd like to talk through an assessment for your child — and how to support the rest of your family through the journey — get in touch with our team today.
FAQS: The Sibling Cheat-Sheet
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Use simple, age-appropriate language that focuses on difference rather than deficit. For example, "your brother's brain works a bit differently, so he needs extra help with some things." Keep it an ongoing conversation rather than a single talk, and use books or videos to help younger children understand.
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Yes. Siblings of children with ADHD or autism commonly feel a mix of love, pride, frustration, jealousy, and guilt. These feelings are a normal response to family life and don't mean anything is wrong. What matters is that your child feels allowed to express them.
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A little shared responsibility is healthy and builds connection, but be careful that a sibling doesn't take on an adult-sized caring role. They should be a child first. Keep caring tasks shared across the whole family.
You can speak to one of our neurodevelopmental experts in a Neurodiversity Navigator consultation. Further information here
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If a sibling's low mood, anxiety, anger, or withdrawal persists and starts affecting their friendships, schoolwork, or sleep, it's worth speaking to a school counsellor, GP, or a family therapist familiar with neurodiversity.
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Signs vary, but parents often notice differences in communication, social interaction, focus and attention, impulsivity, sensory sensitivities, or intense focused interests. You're frequently the first to notice something is different.
If you're concerned, it's worth talking to your GP or seeking an assessment with a paediatrician experienced in how autism and ADHD present in children.
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Wait times for a publicly funded assessment commonly run 12-24 months and can be longer in some regions.
A private assessment usually offers a much shorter wait, which is why many families choose this route to get answers and access support for their child sooner.
Bay Paediatrics is a specialist child neurodevelopmental clinic based in Tauranga, Bay of Plenty, offering ADHD and autism assessment for children across New Zealand. This article is for general information and is not a substitute for individual clinical advice.