"Our father was a servant leader - not only to our family, but to the oppressed, the voiceless, and the overlooked," they say. In the 1960s, Jackson fought for civil rights alongside Martin Luther King Jr, whose daughter remembers Jackson as a "gifted negotiator". US President Donald Trump also pays tribute, calling Jackson a "force of nature" with "lots of personality, grit and street smarts". Former vice-president and presidential candidate Kamala Harris describes Jackson as "one of America's greatest patriots". Jackson built a career around working to politically organise and improve the lives of African-Americans, and became a national force during his two White House campaigns, writes the BBC's Anthony Zurcher. Jackson was diagnosed with Parkinson's disease in 2017 and was hospitalised for observation last November after being diagnosed with a degenerative condition. (BBC)