I am in a similar position only it is my mom who is treating the kids differently. I got together with DSD's dad 6 years ago. Long before DD was even a thought. My mom always treated DSD well, but now that she has a real granddaughter it has changed a bit. I can see the difference. If DD wants something (a certain toy or special food) grandma is right there with it. But recently when we asked for a little help to get DSD to another city to visit a friend who was very sick my mom refused to help. She said that DSD should be collecting bottles and stuff to raise the money. DSD is only 14 and had never had a friend be so sick before. If DD had needed that help it would have been there in a moment. We didn't tell DSD any of this. But she knew something was up. I don't think she likes my mom much cause. But my mom doesn't approve of my choice in husband and I think that comes through when she is dealing with him or DSD. I wish that she could treat her like a granddaughter but they have never developed that relationship. I am not sure if they will now. It makes me sad, but I don't see anything that I can do about it. When I said something it just resulted in a big fight.
So, I have no answers for you, but you have my sympathy!
