The Kauffman Foundation surveyed 550 successful entrepreneurs across multiple sectors, determined by profitability and being named a “high-valued” business by their peers. Their data suggests that most successful founders are in their mid-30s and married with children: "Founders tended to be middle-aged—40 years old on average—when they started their first companies. Nearly 70 percent were married when they became entrepreneurs, and nearly 60 percent had at least one child, challenging the stereotype of the entrepreneurial workaholic with no time for a family."
via Don't Fall Asleep at the Wheel: Successful Entrepreneurs Have Lives | Entrepreneurs on GOOD.