I did some research yesterday but just noticed Carolyn's input.
The PRDH shows Louise as being born on 18 and bapt. on 19 Aug 1789 vs 1794. IT is consistent with the year of death: died on 26 and buried on 27 Aug 1789. PRDH could be in error with regard to the year.
I will check the actual registry.
Their son Francois was born on 12th and bapt. on 13 Feb 1791, also at Longueuil.
Using BMS2000, I have not been able to find marriage records for their children, either under Magnan or Champagne.