Ouch that does suck, I wasn't aware that Microsoft had gotten rid of family accounts. Wonder why they did that. You might want to try e-mailing firstname.lastname@example.org
to try and get some help. No, I'm pretty sure that's not his actual e-mail address but if Microsoft is like a lot of other companies with well known CEOs it might get the e-mail sent to a higher up level of customer support. Another option may be to send a tweet to majornelson or XBoxSupport on twitter to see if you can get some help that way.