To do this change your password then on the xbox, go all the way to the left and go to account.Now go to the right and click sign in on other consoles,Click yes.once done this he will have to sign onto the account with the password but you changed it so there you go hoped I helped.

Well done, you just earned yourself a console ban.

if you didnt do anything than it will be fine

I would think about the word: karma

Believe me i got banned for doing similar things
I found a great website which uploaded 25 accounts for free everyday. I only managed to get about 3 or 4 as the rest got taken by others. They had credit cards, points, downloads, etc so i used some of the points on FIFA. I thought nothing would happen but two months later i get a purchase lock on my IP not my account and a console ban. They cracking down on theft and unauthorised access i wouldnt do it if i were you.