Profile linking.

Accounts can not be linked or transfer items between them, including save data. (Some save data can be shared, but the shared profile can not earn achievements. and there is only a hand full of games that allow that.)

They will have to start from scratch.

If they had Offline profiles on the consoles, you can change them to Online profiles so they can use all there save data.

That is done by logining into signing in with the Account, then going to the Guide button on the controller, then selecting Join Xbox Live.

If you wanted to use the email that are linked to the other Accounts, you can update their emails by following this link.

support.xbox.com/.../manage-live-id

You Should remove those Accounts from the Family plans first before updated WLID emails to free up the slots in the family plan for the offline profiles you are changing to Live profiles.

Glad you have it sorted

Thanks for the help Juan, I was able to get it resolved

yays!

I'm unsure which exact parts of CoC are applicable in this case, But i don't trade / Sell / purchase services for XBL. The only note i have on the blog is that i'm a gamer and that people are free to add me should they wish to play online on some game.

As far as I know you can not transfer achievements, avatar gear, and all that to another account if that is what you are wondering. They'd have to start from scratch if they wanted to create a new gamertag. I don't think you can transfer achievements, gear,
and all that, you'll probably have to call Xbox via Phone Support for more information.