I think it would be good if you had a talk with your daughter. When I was 14 I spent time at my grandparents house often, and I'm thankful that I did because after I turned 16 my grandfather got very ill and died soon after. And I thank goodness that I got to spend the time with him that I did. It did help that my cousins that were my age were also around sometimes, but even when they weren't, I'd watch the price is right and soap operas with my grandma, and helped my grandpa with his garden, etc. It was very hard on all of us cousins, when he passed away, probably because we were all so close with him. There were times we didn't like him, and times that we had great fun with him, but I'm glad that we all appreciate them as much as we do.. sometimes I hear kids talk about when their grandmother passed away or their grandfather, and they say it so nonchalantly, and it makes me so sad, whenever I talk about my grandfather I usually share a funny story, and when my cousins and I get to gether we share the stories as well. "remember when.." kind of thing. So I think you should just talk to your daughter and maybe say she should appreciate the time she gets to spend with them, and not act ungreatful, and since your parents are so understanding, maybe you can tell her to suggest some ideas to make her time there more enjoyable, like a card game, or yatzee or something like that, something that gets everyone involved rather than just the adults (talking about adult things) or just the kids... if you know what I mean? Goodluck and I hope that this helps.
tricia.