Celeste Silas was born about in NY in 1873 and passed away there in 1953. Somehow his surname was changed to "Miller".
His father was in this record: Year: 1881; Census Place: St Gabriel, Hochelaga, Quebec; Roll: C_13221; Page: 46; Family No: 204. Ancestry.com and The Church of Jesus Christ of Latter-day Saints. 1881 Census of Canada [database on-line]. Provo, UT, USA: Ancestry.com Operations Inc, 2009. Citing Jean Baptiste Legasse.
As to how the last name became Miller, John Jean-Baptiste Meunier Lagace Legasy MILLER in this family tree (need subscription to Ancestry.com) shows it might have been derived from Meunier. 
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Celeste Silas is 21 degrees from David Crockett, 36 degrees from Juan Almonte, 24 degrees from Juana Alsbury, 24 degrees from Micajah Autry, 22 degrees from James Bonham, 23 degrees from James Bowie, 30 degrees from Susanna Dickinson, 23 degrees from Patrick Herndon, 22 degrees from James Neill, 24 degrees from Juan Seguin, 22 degrees from William Travis and 22 degrees from Todd Murray on our single family tree. Login to find your connection.