There was a Calvin Warner in Flushing, MI that donated 5 acres, including the school site, to the school district in 1886. The Warner school was built sometime between 1886 and 1890. Also a Warner family listed in the 1850 census for Flushing, MI. There is a B.F. Warner, Mildred, Sarah J. and William George listed in the Flushing Sesquicentennial History book published a few years ago. I have book 2, maybe someone from Genesee Co. can see is those are related to you. In Book 2 there is Barbara, Benjamin and Calvin.