Meetings with a client's family are important to the client's wealth-transfer plan and represent key opportunities for the advisor to establish relationships with the people on the receiving ends of those plans, but they can be a minefield for the advisor to navigate.

"Whenever we're talking to the matriarch or the patriarch of a family, what we're constantly coming across is yes, they do want to have these conversations with their families; however, they don't necessarily want to disclose how much money is in their bank account or how much money their children or grandchildren are going to inherit," said Liz Flint, senior business development strategist at MFS Investment Management, speaking last week at Commonwealth Financial Network's National Conference in San Diego.

"Right there, we already have this communication dilemma," she added.

Flint suggested several topics to jumpstart such discussions, including "what I want my kids to accomplish," "what money means to us," "how to fulfill our aging challenges," "learning more about estate planning" and "how to carry out actual legacy goals."

"None of these questions have anything to do about money. None of them have anything to do with how many assets are going to be transferred, what that inheritance is going to look like. All of these questions have everything to do about values: What are our values and how are we articulating those values to our children and our heirs when it comes to the successful transfer of wealth," Flint said at the conference.

Advisors should select two or three topics to start with, according to Flint.

"Simply two or three of them is going to last you about 90 minutes, and that's typically how long that first meeting is going to last," she said at the conference.

Establishing relationships with clients' heirs is crucial for advisors. Baby boomers are expected to transfer a total of $51 trillion in assets to heirs and charities by 2042, and 70% of heirs don't retain the advisor their parents worked with, according to research from Cerulli Associates, as reported.

While around 91% of the more than 200 advisors with high-net-worth clients surveyed by Cerulli said that clients' spouses or significant others are established clients or otherwise actively involved in the financial planning process, only around 54% said the same about clients' children, according to Cerulli.

"The looming wealth transfer presents a significant opportunity for advisory firms that can adapt to a shifting landscape and evolving wealth demographic," Cerulli high-net-worth analyst Chayce Horton said in a press release accompanying the research. "It remains critical for wealth management firms to have thorough discussions with clients and ensure they have well-designed and adaptable intergenerational plans in place."