Make room for the other version
Ask what the other person understood before assuming that you are arguing about the same facts. For a message about how to support a parent estranged from an adult child, use this factual base: acknowledge the event and practical strain using only information the parent has chosen to share.
Correct the record precisely
Correct only what you can support, acknowledge any real impact, and propose a practical way to prevent repetition. Offer a meal, transport, childcare, advocacy, ordinary company, or another specific manageable help. Make the immediate next step clear enough that the recipient can answer without reconstructing the entire history.
Agree on a testable next step
Do not offer diagnoses, compare children, demand updates, or post about the family. Use medical, safeguarding, crisis, domestic abuse, or emergency services when a parent or child may be in danger. Do not recruit an audience, publish private evidence, or turn a misunderstanding into a campaign about character.