Where do I go from here?

My daughter is spending the week with my bdaughter, they are inseparable. I cant help but have a little jealousy because I would love to spend the week with her... I dont want to smother her or push myself on her, I want to give her space. We are going to to a waterpark next week and I would like her to come, do I need to invite her whole family or would that be asking too much? We are one big happy family and amom wants us to do everything together but I would also like to have some outings with her without them.Also my daughter loves being with her sis so much she said she wanted to move in with her, amom said she didnt know about that but maybe over the summer without talking to me first. The end result will be she will be disappointed that I would say no. I dont want to feel like any boundaries are being crossed, I have always respected mine. I feel like I am being mean by saying that but I am responsible for her and she has a lot of doctors appts, I dont want her being gone the entire summer, I want to spend time with her too.