Howard Buffett (Warren's father) was born in Omaha, Nebraska to Henrietta Duvall Buffett and Ernest P. Buffett, owners of a grocery business. Henrietta was of Huguenot ancestry.

Duvall family history in America began when Mareen Duvall, a French Huguenot, landed in Maryland in 1650; his descendants include Presidents Harry Truman and Barack Obama as well as Warren Buffett and Vice President Dick Cheney. What is this?

https://www.archives.com/genealogy/family-history-duvall.html