As our hobby gets older, so do many of the people who created it. Many simply die, but others have lingering health problems. Jeff Perren didn't contribute much to D&D directly, but he did co-write the Chainmail rules with EGG which led to D&D.
He's had to have a leg amputated but is fortunate enough to have a daughter willing to take him in. However, they need a stair lift and are running a GoFundMe to help pay for it.