If you are an heir, you should receive notice of the admission of the will. You will need to meet deadlines to file a Petition to Contest. Please understand, however, that you will need a basis to contest. Generally, the bases used to contest wills would be incapacity (not able to understand) or undue influence (somebody in a position to exert influence wrongfully did so). If probate is not initiated, then you should initiate it. Fees in a matter such as this are generally hourly. Usually a retainer is required. In the right circumstances, however, an attorney may look to the estate to get paid. Do not delay in seeking additional advice.
