Had my daughter's birthday party today and there were a lot of kids there. One of them gave my daughter a bracelet maker set (already dreading the mess) and my niece starts to open the box! I did not want charms and beads all over the floor with so many kids around so I took it away and nicely asked her not to open up any of my daughter's presents especially without her permission (my kid was outside) my SIL grabs my niece's hand and says "It's ok, it looks like your auntie doesn't know how to share!" Um, wtf? You kid shouldn't be grabbing things that don't belong to them, especially others birthday presents and opening them! I just smiled and said "Nope, I don't know how to share other peoples' presents" and put the rest of the gifts in my daughter's room. I am sick and tired of SIL's constant sniping and I am really sick of my nieces behavior with my daughter's things. They have broken toys before and I wasn't going to let her break a brand new thing! Whenever I ask my SIL to please keep an eye on her kids or ask them to be careful, I get this crap. Stupid passive-aggressive crap. I love my nieces but I can't stand their behavior.Was I wrong?