What was the name of Franklin Roosevelt's disability?

Answer 1

We don't actually know for sure, because knowledge of his condition was very small and limited back in his days.

He was diagnosed with Poliomyelitis on the 25th August 1921. However modern doctors in 2003 looking into the history of Roosevelt believed he actually had Guillain-Barré syndrome.

Which one is true, we'll never know due to the lack of knowledge back in those decades.