When a father dies does the step-mother automatically keep all property and inheritance?

The distribution of your father's estate depends on several factors. If he and his wife owned property as joint tenants with the right of survivorship then his interest automatically passed to her when he died. If your father owned any property in his own name he could make a will and direct how that property should be distributed. If your father lived in a community property state, community property laws would affect how the property would be divided. If your father died without a will the state laws of intestacy would guide the distribution of his property. You can check your state laws at the related question link provided below. Follow the link for State Intestacy Laws and click on your state.