I thought the PBS documentary, The Roosevelts: An Intimate History (2014, rated TV-14), was a fascinating look at this family and the personal struggles each had and how they triumphed despite great adversity.
I never knew how influential Theodore Roosevelt was regarding the national parks or how popular he was. It made me wonder how different world events and outcomes might have been had he had a third or fourth term like FDR? Would World War I have gone any differently and if so, how would the Treaty of Versailles have gone, or the subsequent rise of Hitler and the Nazi party? Look what happened after that.