Happysexagenarian
When I read your post DillPickles a phrase that my grandmother often said came to mind: "^Never apologise, never explain^" and she definitely lived by it! I would probably add to that 'Never back down.' BUT, it's your family and you want to restore some harmony between you, so maybe you should initiate contact and offer an olive branch, but don't take all the blame, just tread carefully. Your DS and DIL were also in the wrong for dismissing your concerns and treating you so badly, even though their attitude may have been fuelled by their own worry, so I think they need to apologise for that. If you could all meet up (perhaps in a neutral place) and talk calmy that might be a starting point. Good luck, hope you can sort it out.
The parents are not in the wrong for dismissing her concerns. They had the situation under control and did not require outside interference.

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