David Cassidy's mother isn't Shirley Jones, but Evelyn Ward, who died in 2012. Jones is Cassidy's stepmother.
Whoops, my mistake. I also know that his father was also famous, but probably not as much as Shirley and David were.
Also, I remember reading an report almost to the year that Glen Campbell entered the last stage of Alzheimers. I hope he can be at peace soon.