I wanted to add that my husband cannot stand his sister and, to be honest, thinks his nephews are brats as well. The one made fun of my daughter's knock off Ray Ban glasses a few months ago (told her she looked cheap like her glasses

--he is 12!) and my husband let him have it. Screamed at him to get away from our daughter. It was very unlike DH. He is calm and quiet. His sister and her family brings out the absolute worst in him. He could not stand her growing up and says she has only progressed to a bigger brat as an adult.
He encouraged me to stop sending gifts long ago and really wants nothing to do with them. He says just because they are blood doesn't mean we have to associate with them. It makes me sad because they are family. I don't want to ignore family.
They are very well off. They never send our children cards for any occasion. They came to our oldest child's graduation party without a gift. Not even an empty card (but she did tell me the shrimp that we served was "chewy").
We have been so good to their kids. And I know it seems petty, but it does hurt to be the giver all of the time and never receive. Not even receive a thank you.
When my husband finds out she emailed wondering where the gifts for her children were, he is going to flip. I will tell him after dinner. He may be washing his hands of his sister and family after this.