There is no formula that guarantees a company will stay in business 150 years, no way to ensure that four generations of family members, and possibly more, will manage the enterprise.

But Rabenhorst Funeral Homes has done both by making participation in the family business optional.

Alvin P. “Phil” Rabenhorst never thought about going into the family business.

“I was going to be a college professor. My father had gotten ill, so I came back after graduate school, took some business classes, started to get interested in business and thought I needed to see what was going on,” he said.

It’s been roughly 40 years since Phil left the University of California, Davis, and a career as an art scholar. He works side by side with his siblings Karen R. Kerr, David L. Rabenhorst and G. Scott Rabenhorst — all LSU grads — in the family business.

Kerr had been a preschool teacher and raised her kids before beginning her Rabenhorst career 28 years ago.

“Women in business were not as common as they are now,” she said. “I don’t think our father ever thought I would get into the business.”

But when her father began giving the children stock in the business, Kerr decided if she was going to own part of the company, she ought to know about it. She started with the insurance company, at the bottom, then moved to the funeral home side and is now a licensed funeral home director.

Devin Lemoine, president of management consultants Success Labs, said multigenerational businesses generally have two things in common: They know who they are and have a strong culture and values, and they’re flexible enough to adjust to changes in the market, whether that involves technology or customers’ needs.

One thing the Rabenhorst family has always been is flexible. Company founder Charles Rabenhorst started out making furniture and cabinets. By the end of the Civil War, he was making more coffins than anything else. He officially launched the funeral business in 1866.

The company eventually left furniture and cabinets behind. These days, the family has two funeral home locations, a crematorium and an insurance company.

Kerr said the funeral business has changed rapidly in recent years, giving customers more options to personalize caskets, with camouflage patterns or panel inserts with sports, hunting or military service themes.

Rabenhorst is getting ready to offer “thumbies,” items that feature a deceased person’s fingerprint or thumbprint. The prints used to be taken with an ink pad or a waxy material but now are taken on an iPad and stored in the cloud. Family members and friends can go online and order jewelry, knives and lighters, among other items, featuring the print.

Families have asked the funeral home to put candy and liquor in caskets, she said. The family of one horse lover asked that a saddle be placed on the casket.

“We try to accommodate our families in any way possible,” Kerr said. “Just as long as it’s legal, we’ll do it.”

One of those accommodations is a reception room. Rabenhorst has set aside space at both of its locations and offers catering for post-funeral get-togethers.

People are more mobile now, Kerr said. Although a parent may have lived in the area, the children often don’t and there’s no home where people can gather after the service.

That mobility eventually may mean that Rabenhorsts will no longer run the family business.

The fourth-generation siblings have seven children altogether, Phil Rabenhorst said. But none are in Louisiana, and so far, the fifth generation hasn’t expressed any interest in taking over the family business.

The family is working with an out-of-state consulting firm on a transition plan, but if anyone has a brilliant idea on how to persuade the next generation to take over, Phil Rabenhorst is happy to listen.

Listening to one another and getting along have been keys to the fourth generation working so well together, he said. Another key has been maintaining control of the company’s stock.

Having an unwieldy number of stockholders can complicate a generational change, Phil Rabenhorst said. The stockholders start to wander off in different directions. Family members develop competing interests. The family business gets sold.

The Rabenhorsts aren’t planning to let that happen.

The family has regularly scheduled meetings to discuss the business, and they frequently talk about transition planning.

According to the Family Business Review, only three in 100 businesses make it to a fourth generation.

Even fewer last a century and a half. On her blog, How 100-Year-Old-Companies Survive, Vicki TenHacken, a management professor at Hope College in Holland, Michigan, lists a half-dozen companies marking their 150th anniversaries in 2016. Two of them are Sherwin-Williams and General Mills.

Kerr believes Rabenhorst is already Baton Rouge’s oldest continuously owned family business (It’s possible that the Heroman family holds the title. The original Heroman, George, started a bookstore downtown in 1837 that evolved into a flower shop).

“We’ve made it to the fourth generation; 150 years, that’s quite an accomplishment,” Kerr said. “In reality, how long can a business continue on?”

The Rabenhorst family isn’t sure.

None of the fourth-generation siblings plans to retire anytime soon, although they could, Kerr said. She is putting her hope in the future.

“We have six grandchildren among the siblings,” Kerr said. “Mine are 6 and 9, so if we can just hang on a little while. ...”

Follow Ted Griggs on Twitter, @tedgriggsbr.