In general, we have travelled with friends and family members. We haven't had any problems arranging the finances. If it is a vacation we're planning, we simply make our own plans and announce to everyone else where we'll be and when. If they want to join us, they do. If they don't, no problem.

And that's how I'd approach it with your SIL. Make your plans then tell her when you'll be there and where you'll be staying. If she wants to stay in the same hotel, cool. If she wants to meet with you in the park, terrific. If she wants to rent her own car and experience a little of the night-life, she's free to do so. We're (almost) always happy to see our family and friends.

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I'm sorry, but I think it's totally rude of her to even suggest that you pay part of her room to have your child stay in there when you where nice enough to let her tag along on your family vacation. My niece lives with my mother and they sometimes go on vacation at the same time we do. My niece usually ends up staying in our room because their room is overcrowded. I would never in a million years expect my mother to pay for part of my room. I wouldn't go on vacation with her if I where you, it will just end up a disaster and ruin your whole Disney experience. I really don't like going on vacation with other people anyway, because I feel like I am obligated to go and do what they want to do, not what my family wants to do.

Ok, here goes. I agree with your sister. Yes, she'd have to pay for the room anyway, but she wouldn't be sharing, she'd have her own room, which personally I think I'd want if I was to go on vacation, no offense whatever intended.

I don't think it was right of your SIL to ask that you pay 1/2 of her room just because your dd would be staying with her. I would think she would be happy to help you guys out and want to spend time with her niece. I would gladly have my niece or nephew stay in my room with me for the week, without having to make my sister pay 1/2 the room.

We went to Disney last month and there were 5 of us total. We stayed at a value resort and got two connecting rooms, one for my dh and I and one for my MIL and our two boys. It was I think $82/night per room. That may be an option for your family of 6, getting connecting rooms and then your SIL would have her own room and she wouldn't have to worry about anyone rooming with her or you having to consider paying 1/2 of her room.

We have traveled and vacationed with friends before and it was a little too close to comfort for us. Same thing with some family members. Just make sure you guys all have a set of rules basically before you even go, like in the pre-planning stages.