After leaving office in 1993, Bush was active in humanitarian activities, often working alongside Clinton, his former opponent. With George W. Bush's victory in the 2000 presidential election, Bush and his son became the second father–son pair to serve as the nation's president, following John Adams and John Quincy Adams. Another son, Jeb Bush, unsuccessfully sought the Republican presidential nomination in the 2016 Republican primaries. After a long battle with vascular Parkinson's disease, Bush died at his home on November 30, 2018. Historians generally rank Bush as an above average president.