How exciting to find someone who is the grandchild of Phoebe Martineau and Francis Gamelin. Do you have records of her parents' names, dates and places of birth, and names of all of her siblings? Some trees on this site have names of children, but the dates of birth don't seem to fit with the date of birth for Joseph Martineau in that he'd be in his 70's when he had his youngest children.
In the hopes that I may help you, and knowing that you may already have this, I note the following information that I found in the NNYACGS publication of records from the Assumption of Mary Parish, Redford, NY. Might I have one of your parents listed? Am I missing any of Phoebe's children?
Phebe Martineau d. 4/12/04  at age 68 Vol. 3, page 374 Spouse of Francis Gamelin
Gumlaw, Phoebe d. Mar 10 1904 ae 67 yrs Geo LaPIER d. 22 Mar 1894 ae 11 d B
BIRTHS (Children of Francis Gamelin and Phoebe Martineau)
Sponsors: Oliver Bisson, Dom. Martineau*
*I believe she was my great great grandmother, married to Jerome Bisson, and the sister of Phoebe Martineau and Elizabeth Martineau. Joseph and Marguerite Martineau were married in Yamaska, Quebec, in 1825. They had two daughter, Matilde and Elizabeth, born 1826 and 1828 respectively. A Joseph and Margaret Martineau are in the U.S. census with children born in New York, one being Phebe. I believe this Joseph and Margaret are the same couple who were the parents of Matilde and Elizabeth, unless there is another couple of the same name and background. Matilde and Elizabeth are not listed in the U.S. with the parents, but they were older and may have been boarding elsewhere or in Canada.
Rose Anna Gamelin
sponsors: George Bisson, Julia Gagner [married each other 6/23/1868]
sponsors: Alexis Bisson and Celanise Tremblay (spouses, marriage date?)
MARRIAGES (Other children of Francis Gamelin and Phoebe Martineau)
Gamelin, Lillie (parents: Francis, Phebe Martineau)
Pierre Lapierre (parents: Peter (dead), Betsie Martineau)
Witnesses were Paul Gagner, Francis Gamelin.
= Is Betsie a nickname for Elizabeth?
= Were Lillie and Pierre 1st cousins?
Gamelin, Pierre (parents: Francis, Phoebe Martineau)
Fontaine, Adele (par. Seraphin, Merentie Lacaille)
Witnesses were William Gagner, Louise Gamelin.
Gamelin, Louise (parents: Francis, Phebe Martineau)
Polydore Pelletier (parents: Narcisse, Mar Gadoua)
Witnesses were Narc. Pelletier, Francis Gamelin.
I hope we can share some info that helps each other out, as well as others who are researching these people!
Submitted by Pamela Wright, firstname.lastname@example.org