Hi Ken, Just wanted to add some info for the next version of the book and your database:
Alfred S Calkins (b 10 Mar 1868), son of Almeron Eldred Calkins (Person 1232 in the book), married Jesse Hawk and they had four children, two show up on the 1900 Ill census: Robert (b. Mar 1897) and "baby". The baby turned out to be Frederick Stone Calkins (b. 30 May 1900) (my grandfather).
Frederick Stone Calkins married Enid Kewin, and they had one child, my mother: Carolyn Kay Calkins (b 26 Aug 1937, d 17 Oct 1984). She was an only child. So this Calkins line ends with Frederick Stone as the last male Calkins on this branch. He died 1 Feb 1971 in Granada Hills, Los Angeles, California.
If you'd like more information on any of this branch, I'd be glad to give you what I have.