Yeah, and I take yours. I hadn't seen your post about her being close to tears, looking beaten. It changes my opinion somewhat, perhaps you were right after all.
I don't think that's relevant. As others have said, if you step in it comes across as a criticism of the parents.
I'd have politely told you that I was the father, would you kindly piss off.
If someone told one off my children off for the way that they were interacting with me, I would politely ask them to butt out.
If I wasn't there, and somebody, again politely, told one of my children off for a justifiable reason, I might thank them. But I would reserve the right to decide if...