Who is Elliot Roosevelt from Eleanor Roosevelt: A Life of Discovery and what is their importance?

Eleanor Roosevelt's father, Elliot Roosevelt, was the one person who fully recognized her charm, intelligence and talents. In return, she completely idolized him. Sadly, Elliot was an alcoholic, in addition to his addiction to pain killers. Elliot died as a result of a bad fall that occurred during one of his drunken binges.