"Surprise! You have a $100 million trust fund!" That is the message at "trust reveal" parties hosted by wealthy families and advisers around the country. Baby boomers, who accumulated unprecedented wealth during decades of economic expansion and stock-market gains, are now passing their mammoth fortunes down. More than $100 trillion will move from older generations to offspring and charities through 2048. Around $62 trillion will stem from high-net-worth individuals, who make up around two percent of all households.