Your Gravel line is correct, except you are missing one generation. There are actually three Pierres in a row: Pierre (born 1755), Pierre (born 1721) and Pierre [baptised as "Pierre-Paul"] (born 1695).
Marie Beauchamp was born and baptised 4 August 1827 in the parish of St. Athanase-de-Beaurivage at Iberville. Go there to find her parents. I suggest you use ancestry.ca's Drouin Collection, as it is the best and most available source, with a scanned image of the actual record.
All Gravels of French-Canadian ancestry descend from one couple: Joseph-Masse Gravel and Marguerite Tavernier, who married at Quebec City on 1 May 1644. So, we are all cousins. We are very distant cousins, however: seventh cousins once removed, according to my genealogy software.
One correction to my previous message: Napoleon Guertin [baptised as "Horace-Napoleon"] was born and baptised on 17 April 1847, according to his baptismal record (parish records of St. Joseph-de-Chambly, Chambly, Chambly County, Quebec; page 10 in 1847, baptismal record #49 in 1847).
I'll correct the burial location in my data base for Horace-Napoleon and Armadulie. Thanks.