Bucky Bush was 79 at the time of his death Tuesday. He is the youngest brother of former President George H. W. Bush and the uncle of former President George W. Bush.
Bush was influential for decades in the Missouri Republican Party, and was active in the presidential campaigns of his brother and nephew. He was also heavily involved in helping a number of St. Louis institutions, including St. Louis University and the Missouri Botanical Gardens.
US officials have offered their condolences to the Bush family on Twitter.