Charles Rouleau and Mary Rudeibuch are mentioned as the parents of Annie Jane Rouleau (b. 18 April 1840 OH bp 13 Jan 1860 St. Francis Xavier d 19 Dec. 1928 Wyandotte bur Ecorse Cem.) in the record for Hyacinthe Riopelle in "Genealogy of the French Families of the Detroit River Region 1701-1936 Vol II p. 1061, item 16, by Fr. Christian Denissen. Books seem to be commonly referred to as Denissen.
Seems odd that she was baptized 20 years later unless she wasn't raised Catholic.
You might want to try the State Archives for probate records (Wayne County 1796-1901) if Charles died before 1900. I would let them know that there is more than 1 Charles and let them know if you want copies of what they find. It did cost $0.25 per copy plus postage and probate records can add up. I paid over $9.00 one time but it was worth it. You can email your request at the following.http://www.michigan.gov/hal/0,1607,7-160-17445_19273_19313--...
The Downriver Genealogy Society has the Roulo name in their surname index:http://www.rootsweb.com/~midrgs/drgs.htm
There is a book by the DAR of Wayne County marriages 1818-1838 microfilmed by the Mormon church. The church has also microfilmed the land records with Grantor/Grantee indices and has microfilms of Wayne County Cemeteries.
The Burton Historical Collection at the main Detroit Public Library has the Archdiocese of Detroit Catholic Church records on microfilm. You would have to either research yourself or hire a researcher. The library is planning on charging a $100.00 annual fee to non residents for the USE of the collection starting August 1, 2004 .
Any possiblity that Charles had two wives, both named Mary? Denissen shows that the Charles who married Mary Henry had 4 children with the 4th one born in 1827. It could be that she died and he remarried or that the family moved out of the area and no other children were recorded.