It might be that someone researching the CADIEUX name could help you, as there is much to be found in census and other records about David Cadieux who married Mary Frances Lloyd, daughter of Harriet Surratt and William Lloyd.
In the 20 Aug 1860 census for Calhoun Co., Albion, Michigan:
Dwelling 656, Family 645:
William Lloyd, 41, breadwinner, personal estate $100, b. Connecticut, married within the year
Harriet Lloyd, age 34, housewife, b. NY
Harriet Lloyd, age 18, domestic, b. NY, married within the year
Harry Bennett, 32, Clerk, b. Germany, married within the year
Mary Lloyd, age 11, b. NY
William C. Lloyd, age 5, b. NY
I'm not sure if the check mark by the census taker noting that William was married within the year is accurate.And it appear that Harriet Lloyd, age 18, may be the wife of Harry Bennett.Not sure.You mentioned that Mary Francis married David Cadieux; I see that record of marriage for October 11, 1865, in Oshterno, Kalamazoo, Michigan.
In the 4 Aug 1870 census for Grosse Pointe, Michigan, Wayne Co., page 5:
Dwelling 36, family 36:
Cadieux, Richard, age 31, laborer, b. MI
Cadieux, Caroline, 27, keeping house, b. MI
Cadieux, Albert, 6, b. MI
Cadieux, Francis, 5 mo., b. Dec 1869, b. MI
Dwelling 37, family 37:
Cadieux, David, 33, carpenter, b. MI
Cadieux, Frances M., 20, keeping house, b. NY
Cadieux, Harriet E., 1, b. MI
This apparently shows Mary Frances Lloyd and husband David Cadieux.Note that Mary Frances named his first child, a daughter, after her mother Harriet Lloyd.
In 1880, David and Mary Frances are still in Grosse Point, but now have children:Harriet, 11; William, 8; Maud M., 6; Josephine, 4; David M., 2; and Florence, 3 months (b. Feb 1880)Also in this census, David is living next to his brother Richard and another brother, as well as a woman who appears to be David's mother, Archange Cadieux, age 71.
David was clearly listed as a Carpenter, so perhaps he helped his father-in-law repair houses?Not sure, since I don't find William Lloyd in the same census records.
I hope this helps a little.If I can help further, please let me know.