In general, you are not responsible for your mother's bills or debts, even though you are overseeing payment. As long as you don't mix your bank account with hers, or sign any documents agreeing to be responsible for her bills or debts, you don't become personally responsible for them just because you are signing the checks, from your mother's account, to pay those bills. Being authorized to write checks from an account does not make you legally responsible. However, if your name appears on the checks, some creditor might mistakenly assume that you are taking responsibility for the debt. If you get any communication from one of your mother's creditors asking you to personally pay one of her bills, let them know immediately in writing that you are merely handling your mother's finances for her, but that you have not assumed responsibility for her debts.