The lawyer who prepared the will cannot be reached. How do we start probate?

The lawyer who drafted the will does not have to remain available for the family to begin dealing with the estate. Start with the signed documents or copies the family has, the current ownership records, and the basic family information, then take those materials to local probate counsel. If the original will cannot be located, counsel can determine what the state's probate rules require to prove a copy or otherwise establish how the estate should proceed.