Mr. Puzo, who says he has set up increasing numbers of quiet trusts in the past two years, notes that it is important not to leave heirs in the dark too long: The beneficiary needs to know his financial situation, and the family needs to make sure someone is keeping tabs on the trustee, he says.

WSJ: Can You Trust Your Kid With $5.25 Million?

And over the last two years, that has meant taking on some powerful interests who had been dominating the agenda in Washington for far too long.

WHITEHOUSE: Weekly Address: Honoring the American Worker