Hi Jean,
My you have been busy! I do believe I have all the information you are citing but will look through it again.
I am using the April 8, 1866 DOB listed for John Christian McMillan from his death certificate. As always this could be incorrect but it was all I had. I sure do wish I could track him down on the 1900 Census too!
I will have to hit my mother-in-law up to see if she has any idea how old he was when adopted. I have never heard any stories about why he ended up adopted by a Canadian family. Only that the family had all girls and wanted a son. Perhaps Cassandra was unable to have any more children.
We had heard the stories of him being a miner but until I found the marriage record we never knew where.
I did find his adoptive sister Elizabeth and her husband Alexander Dyer in Esmeralda County, NV on the 1900 Census but John C was not with them.
My husband and I recently visited the graves of John C, Edna, Elizabeth Dyer, Rebecca McMillan, Cassandra Adair and Mary Goodwin. All are buried at Forest Lawn in Glendale, CA.
Seems the family members who came to the US stayed close over the years. In fact my first clue to a positive connection was the fact that Edna McMillan was the informant on Mary Goodwin's death certificate.
Thank you for taking the time to do such detailed research!
June