Your mother dies with no assets no life insurance and high debt such as credit cards home mortgage car etc you are one of 3 adult children father is predeceased What are your financial responsibilitie?

The assets of her estate (whatever they are and however much there is) will be sold in an estate sale to satisfy her obligations. Any remaining assets will be awarded to her children/survivors. If there are insufficient assets to satisfy the obligations of the estate, the creditors will divide whatever there is and be required to take a loss on the rest.