Here is what I have on Gilbert Moutaw and Katherine LaFleur. I cannot confirm your hypothesis about Katherine , but it sure looks like the two are related. If they lived in the Mendon, St. Joseph County, MI area, they more than likely related. I my case, all families with the surname Moutaw are related. The surname was changed from Mouton to Moutaw by the Mendon family. Many of the surnames of branch families in my tree, still live in or around Mendon, MI.
Descendants of Katherine LeFleur
Generation No. 1
1.KATHERINE (2) LEFLEUR(JOANNAS LeFleur 1) was born 1842 in ,,,Canada, and died 1922 in Mendon, St. Joseph, MI. She married GILBERT MOUTAW 1858, son of FRANCOIS MOUTON and CATHERINE NAVARRE. He was born 13 July 1818 in St. Antoine, Washtenaw, MI, and died 1904 in Mendon, St. Joseph, MI.
Children of KATHERINE LEFLEUR and GILBERT MOUTAW are: i. EVELYN3 MOUTAW, d. 29 January 1871, Mendon, St. Joseph, MI. ii. OLIVER MOUTAW. iii. AVELAID MOUTON, b. 08 September 1862, Mendon, St. Joseph, MI. iv. EMMA MOUTON, b. 17 November 1865, Mendon, St. Joseph, MI. v. CATHERINE MOUTAW, b. October 1868, Mendon, St. Joseph, MI; d. 12 September 1874, Mendon, St. Joseph, MI.