Go to guidestar.com, set up a free account. You can search public charities and private foundations, as recognized by the IRS. The primary purpose is to make public the tax returns and general info of registered charities and private foundations - part of the price of being tax-exempt is the transparency of their tax returns (information returns, more or less) being subject to public inspection. A tax-exempt entity can't ask for public donations, or be allowed to be tax-exempt, if the public can't be sure they are what they say they are.
If you search for words like "liver", you may find some private foundations that are set up to help those needing liver transplants, or have health problems related to their liver. For example, someone who dies of liver disease may leave a will that designates part or all of their estate go to setting up a foundation that helps with liver transplants. Look at the 990-type return, it should state their purpose, which has to be specific to a degree, such as helping people in a certain state that need liver transplants, or such. You can start by searching for those set up in your state. If you find some that may help someone in your situation, it doesn't cost much to contact them. Address and phone number should be in general info, or listed on the 990 return.
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