It owes its wealth to the Walmart company started by brothers Sam & Bud Walton in Northwest Arkansas more than six decades ago. Just three siblings own a plurality of Walmart's 8 billion shares.

The Walton siblings’ late brother John Walton, his son Lukas Walton and wife Christy Walton, lost about $3 billion collectively. Bud Walton’s daughters Nancy Walton Laurie and Ann Walton ...