Friend's Son Transferring Funds from Her Bank Account - Theft and Fraud?

I have a close family friend, she has a son who had access to her bank account. When she set up the internet banking, her son set up the internet transfer option and had his mobile number and he knew the passwords and all the info to the account. He managed to transfer some funds from his mother's account to his account (overseas) then he transferred the funds to his Australian bank account. I need to mention that that family friend bank account is overseas and also her son's (and has an Australian bank account too). My close family friend lives overseas, she is a close friend to my parents (living near them - she is like my aunt).

As I understood, when the son went overseas and helped his mom to organise the banking matters, he obtained all the info to access and transfer authority and then he started withdrawing funds from his mom's account to his account (overseas) then transferred from the overseas bank account to the Australian bank account. My close family friend was not aware about it until later on. He was in Australia when he did those transactions, as I understood the transactions occurred over a period of time when I was sure he was in Australia initiating the transactions .

I am trying to find a way to see if I can help her: Is there any legal method or approach I can rely on, like charging him with committing fraud, theft or anything other (sorry I am not aware of the legal aspects of this, so I was guessing). So the transfer transaction occurred in Australia (over the computer - internet banking), then once the funds were transferred to his overseas account he transferred them to his account in Australia (all through internet banking).

So what can I do to assist my close family friend? Please let me know if anyone needs more info.

Thanks all.

Please note, I was not sure under which section this should be.

Thanks.