I have been with my partner for around 3 years now and she has 2 children from a previous relationship. We do not live together and I see them 2-3 nights a week at most. I have a good relationship with them. I also have a child of my own.
My brother has invited GF, Son and I to his wedding in Thailand for 7 days in september. he is renting a villa for my parents and our other 2 siblings and their partners and kids. He is paying for everything including the flights.
So I have told my girlfriend, she wants to go but her ex is a very unreasonable man. most likely he will say no to having their kids for the time. So I said that he has been given enough notice for him to arrange something. As she knows that he will say no, she has come back with "oh you just got with your son". my response was that her kids have a dad and that he should have them. The conversation ended with her saying that "we come as a package" referring that she would like her kids to come if the ex does not have them. My point is that first of all, we are not married. My brother has never seen them/interacted with them. they have not been to any family events bar my sons birthday around a year ago. the total per person for the whole trip is costing around 11k per person. money isnt the issue here, my brother is wealthy and if he wouldnt cover it, I would happily pay, my only issue is if my brother says no to them coming, and my partner then has an issue with that then it would be detrimental to our relationship. I am very close to my my parents and siblings. What do I do?