<human>: Our 13F Niece is having troubles entering 8th grade at her school and expressed interest in moving in with us, originally she was coming down for 2 weeks to stay with us and play with our kids 4M and 2F.  

Her parents are in favor of this and so is my wife and MIL,  I am not.  I have expressed that I am not in favor of it twice and each time I am messaged/texted from another party explaining to me how it would benefit her greatly to change to our school system, lower class sizes and fresh start for her.  

With the schools starting here soon I am running out of ways to say no and explain to them that I am not going to sacrifice my kids' household to help guide this young lady into acting right and prioritizing on school.  Unfortunately my Niece has had a rough couple of years and my wife is set that we can fix it and make the world right for her.  

I'll answer any additional questions below to try not to drag out the text, thanks to all who respond in advance.

Condense the text into a few key points
<bot>: Wife and Wife's family want our niece to move in with us to give her a fresh start/How do i say no to where they will get the point?