Life Insurance

Although not a  probate asset, check for insurance policies with valuable papers, safety deposit box, call any and all agents or companies they may have done business with for auto and home insurance, investments, retirement planning.

Unfortunately, parents commonly fail to inform adult children of insurance policy's existence. As a result, many policies go unclaimed based on long dormancy periods or lack of awareness. Insurance companies would like to distribute what is rightfully due, but the responsibility to claim benefits lies with the survivors. 
If all else fails try these:

The National Association of Insurance Commissioners "Life Insurance Company Location System" helps you find state insurance department personnel who might help identify companies that might have written life insurance on the deceased. Go to Missing Money for unclaimed policies.