The type of dementia he had - FTD - sounds particularly painful for somebody who had such a strong personality and who clearly loved writing and language as much as he did.
I've put together a JustGiving page to raise money for the leading charity in this area in the UK, with the hope that in Terry's memory a few people might be able to say thank you with a few quid.
https://www.justgiving.com/fundraising/Terry-Jones-RIP
RIP Terry.