Re:Silly Woman
Just before the big puberty hit, I used to manage my mothers landline account as she was far too busy doing other things than parenting.
I can tell you it's not that difficult if you sound remotely like them, speak in a manner that an adult would and know those key bits of information such as Date of Birth, Post Code and Full Name.
I'm now 27 and I'm pretty sure I could still pull it off if I ever needed to. Sorry Claire :(