Brendan McDermid/Reuters President Donald Trump's niece Mary L. Trump is publishing a book in which she'll reveal she leaked family tax documents to The New York Times, The Daily Beast reported. President Donald Trump's net worth is estimated to be $2.1 billion, according to Forbes. Combine that with the reported individual net worths of the Trump children, and the entire Trump family could be worth more than $3 billion. They spend their money lavishly, from a hefty real-estate portfolio and an aviation fleet to designer clothes. Visit Business Insider's homepage for more stories. President Donald Trump's niece Mary L.