Having a pile of money in place of a company, with all of its stress and complications, would seem like a relief. But a company often holds families together by giving members a shared identity and conferring a status in the community established by previous generations.

Without the company, the family’s perception of itself and its purpose can change, and it is often something that members are not prepared for. Their focus was on running the business and then on the sale; little thought went into what comes next.

“This is going to become more and more relevant because of the aging out of baby boomers,” said Michael Cole , chief executive of Cresset, which manages money for large wealthy families. “The key to doing it successfully is how you prepare yourself and how you prepare your family. It’s really a lifestyle choice.”

If families do not do it right, splitting apart is almost inevitable. “A shared business becomes very much a glue,” Mr. Cole said. “When the business is sold, what we see in almost every situation is some family member splits away.”

Mergers and acquisitions involving family businesses are already happening at an increasing clip , said Rick Simonetti , head of wealth planning for Abbot Downing , a division of Wells Fargo. Owners are putting their businesses on the block or receiving unsolicited offers, often for more than what the families thought their company was worth, he said, citing an increase in referrals from bankers working to sell family businesses.