Yes, in My Account you can add someone as your secondary contact. 

This contact will have the same rights as you, the account holder. Your secondary contact is authorised to discuss with us all matters regarding your account including changing plans, making payments, modem troubleshooting and even cancelling the account.
To add someone as your secondary contact, please follow these steps:

  1. Log in to My Account and click on 'My Details'
  2. Under the "My Secondary Contact" section, tick the box to indicate you want to add a secondary contact
  3. Fill in the fields, save and you're good to go