There is a John West, born in September, 1847, who is listed in the 1900 U.S. Census of Frederic, Crawford County, Michigan in the household of Timothy Webster, who is listed as born in May, 1859, in Canada. John is listed as a "brother-in-law." No spouse is listed.
1900 U.S. Census, Frederic, Crawford County, Michigan (E.D. 0078), pop.sch. 2B (handwritten), dwell. 39, fam. 40, FHL 1240708.
https://www.ancestry.com/imageviewer/collections/7602/images/4120220_00311?usePUB=true&usePUBJs=true&pId=64323097
I tried to pull it up on familysearch.org without success, probably because of my lack of familiarity with that site, but I bet that you - who are probably more gifted on that site than I am - can find it.
I wonder if that is your John and it if it makes sense to focus on the Webster family as his possible in-laws.
If so, I wonder if the marriage took place occurred between 1880 and 1900, when we're all hampered by lack of censuses and, possibly, if it took place in Canada