I would be furious - I'm so sorry you're dealing with this!
You have taken the high road in every way possible, and it seems like they are still out to punish your entire family. I understand them needing a moment to recover, as they are attached to their nice things, but their behavior is getting more and more rude by the minute.
I know you can't keep a toddler from blurting things out - but the fact that this was her greeting (AND that all your friends were in on the joke, apparently) tells me her parents are making a giant deal about this to anyone who will listen. At the total expense of your DD's feelings! What is more important here, things or people? Clearly, your friends have decided it's the former. They have displayed none of the sensitivity or tact you've employed at all - and regardless of whether they foresaw the problem or not, they have to accept *some* responsibility for introducing the weapons of mass destruction!
I don't think these people are really great friends, honestly. I can give them leeway for an overreaction, but this is just rude and inconsiderate. Shoving the video monitor into your hands...that seems clearly judgmental, but even if that wasn't the intention, taking away crayons?!?! When you are all right there on the scene???
Clearly, they want you and your DD to feel "punished" - and persecuted. For one toddler mistake, that was partially their fault (for providing the markers AND for not supervising).
Maybe it merits one last discussion - saying, "look, I know these things are important to you, and I've offered to do everything I can to fix/clean/replace them...but where does it end? Will it ever be good enough? They are just kids and you are partially responsible for this, too. What is more important in the long run to you - things or our friendship? Because I'm getting the message that it's the things, and that we are no longer wanted here. I won't come over when I'm not wanted or where my DD will be treated like a criminal." Maybe set up new house rules or make it clear you will supervise your DD so they feel more comfortable. But I'm not sure that's possible...
At the end of the day, make sure you are sending the right message to DD - we all make mistakes, and we deserve a chance to learn from them and be forgiven. Not to be treated horribly forever after.
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