Child accounts on Microsoft live

I'm a UK based Mac user.  My daughter has a new Windows phone so I have created a new Microsoft live account for her, and one for myself.  I've looked through discussion threads and followed all the help options I can find to link these accounts, nothing works.  I'm not prompted for any permissions when I log in using her details even though I've set her date of birth correctly (she's 11).  I do not want to set her up on her new phone until I know I can link these accounts.  When I log in to my own live account, there's an option that says 'Kids accounts' and 'you do not have any child accounts' but there's no option or menu anywhere to prompt me to create one, or to link existing accounts?  Frustrated.com!!  Can anyone help?  Thanks.