By Lisa Ingram, President of White Castle System, Inc.

Nearly 35 percent of Fortune 500 companies are family controlled and significantly drive the American economy. And, according to the Conway Family Business Center, family businesses make up 64 percent of U.S. gross domestic product, generate 62 percent of the country's employment, and provide 78 percent of all new job creation.

However, only an estimated 3 percent of family businesses operate at the fourth-generation level and beyond.

At White Castle, we're proud to say we've beat the odds. We've been family owned since 1921. That's more than 90 years, four generations, and an abundance of important lessons about what it means to be a family running a business together.

From our founder, and my great-grandfather Billy, we learned the value of taking care of our team members and our communities. He offered our team members health insurance in 1924 – practically unheard of in the service industry – followed by group life insurance policies in 1927. He created the Ingram-White Castle Foundation, which has awarded more than $31 million in grants to support programs that serve disadvantaged students and help them achieve academic success and scholarships for team members and their dependents.

My grandfather, Edgar, reimagined the value of food quality and business integration. Under his leadership, our company opened new bakeries, where we make and distribute the buns for our iconic Sliders, and focused on fine tuning our operations to meet the evolving needs of our customers.

Bill Ingram, or, as I call him, Dad, brought about unprecedented decades of growth and innovation. Under his leadership we grew the number of restaurants from 150 to nearly 400. We launched the retail foods division, which put our products in grocery stores nationwide. And, he challenged us to ensure we continued to meet the changing tastes of our customers by encouraging menu diversification.

Each generation has left an indelible mark and has continued to build our business. Here are some thoughts you might want to consider for your own family business:

Make your team members part of your family, especially those you are not related to. As Billy demonstrated to us, instilling benefits – even when you don't have to – shows team members you care about them. Loyalty and longevity – even in an industry with traditionally high-turnover rates – provides a solid foundation for growth and benefits both parties. Focus on areas of growth to build the business for the next generation. Each generation of leaders sets new goals and works with their team to seamlessly achieve results. The family leaders know, this is the best way to strengthen the business foundation for their children and grandchildren for years to come, and as importantly, future generations of team members. Honor the traditions of the past, but leave your own mark. As a member of the fourth generation, I know we are already envisioning what's next and how we can put our own unique mark on a business with more than 90 years of history. And, we're encouraged to do that by the current generation of leaders. If a family member is interested in the business, let them experience it from all aspects. My dad, my cousins and I all know what it's like to steam-grill a slider as well as how to market a new product or develop ideas to build the business. Every role and every aspect of a restaurant is critical to our success. There can be no sense of entitlement and nothing is owed to you. Your hard work and your passion for the business matter more than your last name and are what determines your value to the company. Encourage outside experience. Our family employment policy requires that family members have five years of relevant experience outside of White Castle before being eligible to be considered for an opening. Those with advanced degrees, such as an MBA or a law degree, need to have three. It brings fresh perspectives, experience and improvements to our business.

To pass on a thriving business to the next generation of the Ingram family will be my generation's greatest accomplishment, and we'll have my father, his father, and his father's father to thank for the tremendous lessons and opportunities they have left us.

Lisa Ingram is president of White Castle System, Inc. Read more about her work in this 2014 Q&A.