Exactly. How can you not get upset when your child looks at your with hurt eyes? At one point my son climbed up in my lap and whispered "do they think I'm a bad kid?" and my heart just ached for him. That is what he took from her behavior, that she thought he was a bad kid because she was constantly telling him he could not play with anything.
So yes, I was angry about it because I am a mommy. He forgot all about it and was crying when we left because he was going to miss his cousin.
Sound like a sweet kid. I guess we understand and some just don't get it.

Who doesn't have children who've been treated like crap by someone from time to time? Nobody likes it. But that's when you limit your time with those people. And if it happens to be family, well that really sucks. But life goes on. It's a good teaching moment for your own children. ("This is why we don't treat people this way".) Not everyone they encounter in life is going to be nice to them, share with them, compliment them, protect them, etc. That's just the way life is. 
as if nobody else here ever had a kid that wasn't treated well. Granted, I'm sure you have your "situations" you've dealt with, but so do the rest of us. I don't know anyone whose kids it hasn't happened to.
when mothers start talking in terms like that. Just stick to the facts and others will take you more seriously.
