Very sorry for your loss, Cam. And sympathies to Haird. My Grandmother also suffered from Alzheimers but fortunately, did not show serious symptoms until her 90`s.
Glen is and was a true gentleman though he had his demons. I met him when I was seven. Before he became a star, he was the top session player in Hollywood / Los Angeles. My Mom sang locally and had met Buck Owens who produced some singles and ep's for her. Glen was the session leader on these recordings and was as nice as could be. In the nineties and later, he could often be found at the Paradise Cove Restaurant in Malibu on their jazz nights. I talked with him a couple of times and he remembered Mom and was kind to me. I last saw him perform in 2011 with his son and daughter at a fund raiser for military families.
Jimmy Webb, who wrote many of Glen' hits (and the 5th Dimension) has been touring with Johnny Rivers (Secret Agent Man, Memphis, Summer Rain). They both tell some great stories about Glen (and others) in their show. Definitely worth catching if the opportunity arises.