Are there any long term ramifications in separating teenage siblings who want to live with different parents after a divorce?

My ex wife and I separated 7 years ago and officially divorced 5 years ago. We had three kids together. They are now 16, 15, and 13. The older two are boys and the youngest is a girl. I first moved a couple of towns over and got the kids every weekend. Last year I moved to the same town as their mother. I'm about 3 blocks away from her house and it has been better. It's easier to go and see the kids in school plays, concerts, and sports. They can all walk or ride bikes to my house during the week.The 15 year old asked last year if he could move in with me instead of living with his mom. Nothing major happened but the house is a lot more noisy. His mom and stepdad have a 2 year old together. He has to share a room with his brother at his mom's house and hates it. They are very different and don't get along that well. We told him that he could move in when January started but my 13 year old decided that she wanted to live here as well. She is very close to the 15 year old. They are 20 months apart and hang out together a lot. Both of them play sports, as did I growing up so we all bond over that. Their older brother, mom, and stepdad don't care for sports and don't go to the games. We have more structure at my house. The kids complain that their older brother gets to spend all day on the computer playing video games and their mom does nothing about it. They'll come over to practice a speech or have me read an essay for them before they hand it in because their mom won't help them. They also don't want to invite friends over their mom's house because it's unorganized with all of the toddler's toys in the living room.My ex wife was okay with the 15 year old moving in with me at first but changed her mind when the 13 year old wanted to come too. She says she is worried about the younger two becoming closer while their older brother falls out of the sibling relationship. We are 3 blocks away and we would alternate weekends. She would take all of the kids one weekend and I would take all of them the alternating weekend.Is this a terrible idea that will end up ruining their relationship with their older brother? via /r/Parenting http://bit.ly/2Dx7Wny