My other children resent how much attention the ADHD child gets. They're right.

She told you the truth about your family, calmly, at ten years old. Take that seriously — and also notice that a child who can say that to you is a child who still trusts you. That is not a closed door.

What she is actually carrying

The sibling who copes tends to carry a specific set of things. Less of you, because the loudest need wins the hour. Embarrassment in public, followed by guilt for feeling embarrassed. Sometimes fear, if there are explosions. And often a quiet, unspoken job: be the easy one, because they can't manage two.

That last one is the heaviest, and children take it on without being asked. It looks like maturity. It is often something closer to self-erasure — and it frequently shows up years later, so it is worth interrupting now.

What to do

1. Tell her she is right. Not a defence, not an explanation of his needs. "You're right. He takes up more of me than you do, and that isn't fair to you. I'm sorry. I'm going to change some of it." Being believed by your parent is worth more than any adjustment that follows.

2. Give her time that is hers, scheduled and protected. Twenty minutes, most days, or an hour a week that is on the calendar and does not get cancelled because of a crisis. The predictability is the active ingredient. If it is always the first thing sacrificed, it teaches the opposite lesson.

3. Notice her out loud, for things that are not achievements. She has learned that being fine makes her invisible. Undo that deliberately: "I noticed you sorted that out on your own", "I like talking to you." Not praise for being easy — that reinforces the job. Attention for existing.

4. Explain fairness honestly. "Fair doesn't mean the same. It means everyone gets what they need." Say it, but do not use it to close down her complaint — if she is getting visibly less of the good stuff, the sentence is a cover story rather than a principle.

5. Give her somewhere to put the ugly feelings. She needs to be able to say "I hate it when he ruins dinner" without being corrected into loyalty. Feelings that get corrected go underground; they do not disappear.

6. Protect her things and her space. A shelf he cannot reach, a lock on the door, a toy that does not have to be shared, a friend visit he is not part of. Children who feel their edges are respected are far more generous with everything else.

7. Do not make her a co-parent. "Watch him for a second", "you know how he gets", "don't wind him up" — small on their own, corrosive in aggregate. She is his sister, not staff.

What not to do

Do not reduce what he genuinely needs in order to even the ledger. That helps nobody. The answer is not less for him — it is more that is actually hers, and honesty about the imbalance while it lasts.

What she gains

Siblings of children with ADHD often grow up unusually perceptive, patient and quick to notice when someone is struggling. That is real, and worth naming to her. But it should be a by-product, not the rent she pays for her place in the family.

When to look further

If she seems anxious, is perfectionistic to the point of distress, has become withdrawn, or is frightened of her brother, please speak with your paediatrician or a children's counsellor. The sibling who never asks for help is the one most likely to need someone to ask on her behalf.