My mother just pass July 2, 2008 my question is do we have to pay her credit bill off.

First its not a good idea to piggyback your question on someone else's. This can lead to confusion. You should start a new thread. So I've moved your question to its own thread.

My condolences on your loss. YOU do not have to pay this debt, but her estate does. The executor of her estate needs to determine what assets she left. From those assets her outstanding debts need to be paid. Anything left over can then be distributed to her heirs. If the assets don't cover the debts, then the creditors are out of luck. Simply return the bills marked deceased.