He suffers from a from of Alzheimer's called "posterior cortical atrophy".
It is a rare form, and unlike usual Alzheimer's, it does not deteriorate memory and such but rather affects the vision.
IE. The patient can speak and remember fine, but has difficulty writing or reading.
Terry Pratchett had one daughter named Rhianna Pratchett.
Terry Pratchett's cat is called You.
Terry Pratchett's birth name is Terence David John Pratchett.
Terry Pratchett was born on April 28, 1948.
Terry Pratchett was born on April 28, 1948.
Terry Pratchett's motto is 'Noli Timere Messorem'.
Terry Pratchett stood at a height of about 1.73 meters (5 feet 8 inches).
The duration of Terry Pratchett's Hogfather is 3.15 hours.
Terry Pratchett was knighted during the 2009 New Year Honours.
Terry Pratchett's Going Postal ended on 2010-05-31.
Terry Pratchett's Going Postal was created on 2010-05-30.
As of today (June 26, 2013), Sir Terry Pratchett is still very much alive.