Descendants of Gilles:his children were married over 240 years.There is potential for numerous descendants.Researching on a downward manner if quite a job.it would be best for you to pick some Bertrand and then find out through marriage records if they are desc. of Gilles.
Amable was born in 1739 and Jacques in 1752.No marriage record in Québec for either of them.
Military records:do you have reasons to believe that they were in the military?Such records would be time-consuming to access.Do you know under what circumstances they ended up in Louisiana?There is no indication that they would have gone to Acadia.Jacques would have been only 3 at the time of the deportation of the Acadians.
I believe that they enlisted as voyageurs to re-stock the French forts in the Great Lakes area and travellled the Mississipi River down to Louisiana.This is the hypothesis I have made for a Morin who ended up in Louisiana at about the same time.