UPDATED: John Walton, 2nd Son of Wal-Mart Founder, Dies in Plane Crash

John Walton, the second son of Wal-Mart Stores Inc. founder Sam Walton and member of the retail giant's board of directors, died in plane crash in Wyoming Monday afternoon, the company said in a news release late Monday evening.

Walton, 58, was killed at about 1:20 p.m. when the ultra-light aircraft he was piloting crashed shortly after take-off from the Jackson Hole Airport in Grand Teton National Park in Wyoming. He was the aircraft's only passenger.

On Tuesday, the Walton family said in a news release that the funeral would be private and did not say when or where it would take place. It asked that in lieu of flowers, memorials could be made with three organizations, the Alliance for School Choice in Phoenix, the Children's Scholarship Fund of New York City, and the Teton Science School of Kelly, Wyo.

A member of the Wal-Mart board since 1992, he worked as a crop duster in the 1970s and as a boat builder in the 1980s and 1990s. Recently, Walton formed the holding company True North, which includes advanced composites, boat building and venture capital investment businesses.

Walton also served in the U.S. Army Green Berets as a medic during the Vietnam War. He was awarded the Silver Star for saving the lives of members of his unit while under enemy fire.

As a member of the Walton family that controls Wal-Mart Stores Inc. of Bentonville, John Walton was among the world's wealthiest people, worth an estimated $18 billion. He held about 12 million shares of Wal-Mart stock. He also owned a 25 percent stake in Arvest Bank Group of Bentonville, headed by his brother Jim. He was heavily involved in the family's philanthropic organizations and efforts to improve K-12 education.

In November, Fortune magazine profiled each member of the Walton family, including John Walton. The full profile is available online for free here.

Walton is survived by his wife Christy and their son, Luke; his mother Helen; two brothers, Rob and Jim; a sister, Alice; and their families.