In the book's own words, not ours, with obvious scanning errors fixed. Families often supplied these stories to the publisher, so check key dates.
Born 1840
From History of Crawford County and Ohio : containing a history of the state of Ohio, from its earliest settlement to the present time ... a history of Crawford County ... biographical sketches, portraits (1881)
OLIVER MONNETT, farmer and stock-dealer; P. 0. Bucyrus; was born in Marion Co., Ohio, Aug. 12, 1840, the son of A. Monnett, Esq., whose life appears in this work. He was raised in Marion and Crawford Cos., Ohio, and was married to Miss Etta, daughter of Charles Reamer, Esq., of this county, and formerly of Pennsylvania. To them have been born two sons and three daughters — Lorain H., Dimma, Milla, Charles A. and Emma. He owns 954 acres of land, all well improved, on which is built one of the best houses in the county. Mr. Monnett is extensively engaged in stock-raising, often having over 1,000 head on his farm. He is favorably disposed toward all Christian denominations, but is himself a member of the M. E. Church.
As printed in History of Crawford County and Ohio : containing a history of the state of Ohio, from its earliest settlement to the present time ... a history of Crawford County ... biographical sketches, portraits (1881). See the original pages. Wording is the original; obvious scanning errors have been corrected, and a few may remain.
Their biographies name Oliver Monnett: Elias Stiger (b. 1857)
The printed record stops around 1881. We trace your line from there down to you, with every source cited.