The Democrats' presidential candidate Kamala Harris was not supposed to appear at the party's convention until Thursday.
But ahead of President Joe Biden's planned Monday speech, she made an unannounced appearance.
Joe, thank you for your historical leadership, for your lifelong commitment to serving the nation and for everything you will continue to achieve. We are eternally grateful, said Harris.
Even Hillary Clinton, who was the party's presidential candidate in 2016, honored the 81-year-old as a "hero of democracy both at home and abroad".
He shows what it means to be a true patriot. Thank you for lifelong service and leadership, said Clinton.