You can however transfer the level 70 character to a new account setup in your name since your last name is the same.

"Who is eligible for account to account transfers?
Transfers between accounts are only allowed between one account where you are the owner to another account where you are the owner. To initiate an "account to account" transfer, you will have to answer the 'secret question' for each account, and the last name of each account holder must match. "