Legal Question in Real Estate Law in Maryland

Your question is extremely vague and therefore difficult to answer. I'm going to assume you are the executor (personal representative) of an estate, and you can't locate one or more heirs. There are companies which specialize in locating missing heirs, and if you haven't already done so you can engage one of them (search "missing heirs"). You can also place an ad in a newspaper that circulates in the area of their last known address. If all this fails, you can petition the probate court to declare the bequest forfeited to the residuary legatees. You will have to demonstrate that you've made all reasonable efforts to locate the missing heir.