“All of those notifications can prevent problems that supersede money problems,” he said. Without proper instructions, those decisions “can blow up and result in siblings not ever talking to each other.”

Wealthier people tend to rely on advisers who are privy to a raft of information to help them, especially when it comes to tax planning, which could become more urgent if President Trump’s proposal to repeal the estate and other transfer taxes is passed. Adam von Poblitz, head of Citi Private Bank’s North American trust division, said the repeal of a tax that took 40 percent of a couple’s assets above the current $11 million exemption would increase the need for creating a trust because more money would pass to heirs.

“You need trusts to protect the assets from creditors but also from the beneficiaries themselves,” he said. “That protection aspect doesn’t go away” if the estate tax is repealed.

Not planning for the expected can also cause unnecessary confusion and stress.

“There’s a growing emphasis placed on how do you want to live the end of your days,” said Rachel J. Sherman, vice president of client service at Market Street Trust Company, which began as the family office for the founders of Corning Glass Works. “It needs more attention. People don’t want to be a burden.”

Monette Booth, 73, who lives in the Virgin Islands, said she had learned from her mother and aunt to keep her affairs in order. They “stressed to us children that life is never guaranteed and one should always plan for the future,” she said.

After her husband, Peter, a retired Corning executive, died in 2011, she stepped up her planning to ensure that she could grow old where she wanted, that she would not burden her relatives and that her assets would eventually be disposed of as she wished.

“For practicality and having no children, I recognized that at some point in my life, I will need help,” she said. “It’s taken a load off my mind to have made the decision.”