B.R.
Wow, A., I feel for you. A lot of this behavior is typical though when the first grandchild is no long the only grandchild. When my nephew had a birthday (this was when he was the first) both sides of the family were invited from cousins to grandparents. It was a literal zoo and don't get me started on the massive amounts of presents for a baby that could care less.now that there are around 20 grandkids, many of them don't ever get a visit on their birthdays unless it is convenient. However, it also sounds as if there is something else going on with your inlaws. How they act around and nurture children seems to be a theme. Its easy for a grandparent to just give in as they know the child is leaving soon and the fact that they refuse to have your son over may be a defense mechanism of theirs to ultimately win the argument by not having it in the first place. They want to be good grandparents but the don't know how to say no now that your son knows how push their buttons. Personally I would speak to your husband first to make sure you are both on the same page and then son together with your husband to let him know this behavior is unaccceptable. Then I would write a formal written letter to the grandparents making sure that it is non threatening, but expresses your concern about them not having your son over and you are worried about his behavior...not theirs (you can't change their behavior and trying to will only shut them out). I would say nothing about favoritism though, they may like your niece better for the moment for the reason that they havent ruined her behavior yet. Anyway, just a recommendation, you are the mother of your family and you will know best in the end (oh, and if you are religious do not forget to pray about it).