You will need to consult with an attorney. You may need to petition to remove your brother as executor.
Legal Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on since each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship. A lawyer experienced in the subject area and licensed to practice in the jurisdiction should be consulted for legal advice. Circular 230 Disclaimer: Any information in this answer may not be used to eliminate or reduce penalties by the IRS or any other governmental agency.
You may petition the court to force the sale. You will need an attorney to do this. Sometimes the threat of litigation will be enough to get things moving. Consult a probate lawyer.