Forcing little children to log into XBOX Live with a UserName and Password ? I absolutely HATE this feature! Why can't you just allow them to log in under the Parent account?!?!?! Instead, now the parents have to remember a separate set of email addresses and passwords for each of their children, which is absolutely ludicrous!
Please stop trying to force your security problems down our throat and just make XBOX easier for everyone to play and operate. That includes for kids as well as their parents!