Gold Business account linked to mother's cheque account - this is NOT her account

Good morning. I assist my mother with her banking and downloaded the FNB app on her cellphone. We noticed that apart from her Savings and cheque account, she is also linked to a family member's Gold Business account from which she apparently can move money around should she wish so. She has never requested to be linked to this account, nor are we aware that the family would have requested this, and the only "link" there could be is that she receives a monthly salary from the family's business. This is clearly a mistake and the family will no doubt not be happy that we have full access to their business account and we are not sure if they also now have access to my mother's account.