Family trip

My husband, my 3 babies, my mother and myself will be having a trip to DR to see my BIL his wifes and their babyboy.

Little back story: my hubby is 1 out of 12 kids, I've known his whole family for over 10 years. One of my BIL "black" has been my bestfriend for several years. At one point he lived in my mother house for a while before me and hubby got married and moved out. So we are all very tight. 4 years ago my BIL got deported. the last time i seen him was a few weeks before he got deported in jail. He met our daughter but not our boys. So hubby and i planned this amazing vacation for him to met our 2 youngest and for us to meet our nephew.

We were all so excited but then hubby lets his other brother 'Jay' know we leaving on vacation to see 'Black' and his family. He instantly says we should take his son. I looked at him and told him he was more than welcome to come but we have 3 of our own and wont be taking any other kids because this is our first family vacation. He tells hubby he found it ridiculous because i was taking my mom. I told him my mothers a grown women who can care for herself. She also wont be staying with us, she has plenty of friends she will be visiting. We had a small back and worth and hubby feels like i should consider bringing him. I said i would think about it but my answers still no. I don't want extra responsibilities specially because its a different country.

The little boys 6, he tends to cry for his dad when he staying the weekend with us and we only live 10mins away from him so how will he react being so far away? He has bad eating habits so he will only eat what he wants, which his dad is fine with but I'm not Rich so i can't eat out everyday. His dad will pay for the ticket but believes all other cost should be paid by us because "he's our nephew to" And not that it matters but he's went to DR several times already. Am i being selfish for only wanting to go with my kids?