Hi Don,
I have the same reference material, the Sources book. The only possible answer about Jason and Minnie from what I know from my father's knowledge of his great-grandfathers family would be that Jason and Minnie did not come to MI when Walker & Sophia came with John W, Robert A and William. My father knew his grandfather(John Warren)and Robert and William so for me that casts doubt on whether they were actually siblings(possibly other family members?)as he has never mentioned it. According to my father's notes John Warren came to Cadillac, Mi at age 18(about 1878) but no indication if that was actually when everyone came to MI. John Warren began working for G.R.&I. railroad beginning in 1882 for 49 years and the family moved many times over those years between Grand Rapids, Cadillac and Petoskey. John Warren and his wife Almira Adell(Mason) are both buried in Restlawn Cemetery, Grand Rapids, MI. Alice Griffin is the name I remember seeing when I looked for info on Louis previously. I have no idea why the marriage license shows Louis's parents as Nelson and Mary Jane(Unless he too stayed behind with other family members as he would have been the youngest). I have the actual newspaper clipping of Louis's obituary and at the time of his death I believe there were two newspapers publishing in Grand Rapids.
Tom