Though you don't actually say this, from your question, I assume that your sister is the personal representative, executor, or administrator of the estate. If so, then as a beneficiary--someone with a real financial stake in the estate and its management--you can ask for an accounting. The personal representative, etc. has a fiduciary duty (an obligation imposed by law) to manage the estate for the good of the heirs and beneficiaries, and to use the degree of care and skill in doing so that a reasonable person would use in managing his/her own assets. When there is reason to doubt that the personal representative, etc. is doing this, the heirs and beneficiaries can file a legal action in court (probate/surrogates or chancery court--the clerk of the court can advise you as to which) seeking an "accounting"--literally, to have that person "account for" her actions. If the court concludes that she acted disloyally and/or unreasonably carelessly, the court has the power to undo certain of her actions, to remove her as personal representative, etc. and replace her with someone else, and/or to require her to personally reimburse the estate (and therefore the heirs) for certain losses or wasted expenses. This type of suit is considerably more procedurally complex than, say, suing in small claims court over a fender bender or unpaid bill. You are strongly encouraged to retain a probate or estate attorney to help you.