Whether or not there is a Will, an executor/personal representative/administrator owes the estate that they are overseeing a "fiduciary duty". This means that they must administer estate matters in a competent, fair and honest manner; this includes no self-dealing. Accordingly, if the administrator of the estate in question has wrongfully taken estate assets for themself and/or family members there are in breach of their duty. At this point, the heirs of the estate can bring an action aginst the administrator for the return of the items taken and for financial reimbursement for any items that are not returned. They can consult directly with a probate attorney for more details or they can contact the applicable probate court.