You can check this site https://www.securesafe.com they have a function in case you pass away to send passwords or documents to a trustee

From their website:
Data and passwords can be securely and safely stored for your family.

    Save your documents and passwords in your SecureSafe and leave contact details for recipients of certain information should something happen to you. Then determine which files and passwords you want sent to certain people.
    The data inheritance feature is simple and easy to setup.

The basic service is totally free!