They ruined their sibling's special moment again
ADHD parenting moment
When the ADHD child could not hold regulation through the heightened emotion of someone else's celebration, the sibling lost their moment. Today, do not explain the ADHD. Just acknowledge the loss to the child whose day it was: 'That was your moment and it got interrupted. I am sorry. That was not fair.' The explanation can come another day. Right now they need their disappointment validated, not reasoned away.
What to do right now
The birthday party, the concert, the sports day. It was supposed to be about the other child and the ADHD child could not hold it together. Everyone is upset. The sibling whose moment was ruined needs to hear: 'That was your moment and it got interrupted. I am sorry. That was not fair.' Do not explain the ADHD. Just acknowledge the loss. They can understand the explanation another day. Today they need their disappointment validated.
What your brain just did
Your body
The special moment was interrupted. The sibling whose day it was is devastated. You are managing guilt across two children.
Your brain
The ADHD child could not sustain regulation through the heightened emotional context of someone else's celebration. The sibling experienced loss of their moment.
What this did
Validate the sibling's loss specifically: 'That was your moment and it got interrupted. I am sorry.' Do not explain the ADHD today. Today they need their disappointment acknowledged.