Managing an account: Checking or savings account

There are 3 checking account with my name associated with them. My husband 's, myself and my sons. My sons had a child account and when he became an adult my name dropped off his account. I can't call and ask anything about his account, no information can be given to me when I call. This is what was told to me when he had fraud connected to his account. Since the fraud on his account, if he doesn't have the funds for his car note or insurance they will reach to my husband 's account and take the money out. This has happened multiple times. We called about this. They said. Because my name is connected to all 3 accounts. Which is not correct. They never go in my account to take funds, only my husband 's. My sons name is not on my husband 's account so they should not take money out of that account for bills associated with another account.