How do I change the downloadable content age restrictions on xbox live?

My mom is fine with it an all but whenever we try to go in and change it so I can downlaod Mature (17+) game demos it always ends up changing nothing. Can anyone give me a detaield, step by step process so that I can? ThanksHow do I change the downloadable content age restrictions on xbox live?You have to change the Windows Live account your XBL account is linked to. Change it to one with an age set over 18.