Sign in to My Virgin Media, go to My Profile and/or Manage Accounts depending on whether the account concerned is your primary account or an additional one. Select the account concerned and then click on Change to the right of password if a primary account or View/Change then change to the right of password for secondary accounts.
If the above doesn't help and the account does not show under manage accounts post back and tell us a bit more about the account history.
_________________________________________________________ Graham I am a VM customer. There are no guarantees that my advice will work.
As a Very Insightful Person, I'm here to share my knowledge. I don't work for Virgin Media.
Now is a good time for your son to check the settings on his account - the autoforward, filters, etc. Just to be sure that nothing bad has happened. And why not anyone else who has an account under your control - please do this so none of you suffer any consequences.