Those are actually Sam Waltons nieces his brother Buds two daughters but still heirs though.
Heirs include Sam's three living children Rob, Jim, and Alice. Daughter in Law Christy her son Lucas and Buds two daughters Ann and Nancy. Worth 247 Billion according to this article -
#1 Walton family on the 2024 America's Richest Families - The Waltons are the richest family in America thanks to their stake in Walmart, the world's largest
www.forbes.com