Louis Aubert, the brother of Guillaume (Guillaume Daoust's maternal grandfather) was the procurator of the seigneurie of Sissonne and the husband of Jeanne Cordieu. Guillaume Aubert's 2nd wife was Marie Cordieu. Were Jeanne and Marie Cordieu sisters? Jeanne was the daughter of Nicolas Cordieu (commissaire des tailles of Sissonne) and Jeanne Vincelet.
Jeanne Cordieu is therefore Guillaume Daoust's great aunt!