He had a son, Jean Souffron, first a man of arms in the German Boissy Regiment before becoming a lawyer in the Bordeaux Parliament [fr], and a daughter, Madeleine.
He also had a brother, Eyméric, ordinary commissioner of the king's artillery, and a sister, Madeleine, who married Domenge de La Porterie, master mason in Marmande who built the Villeneuve-d'Agen bridge.
In P. Palanque's article on "Pierre Souffron, master architect of the city of Auch" he attributes to his brother titles that belong to him.
He was working on the cathedral of Sainte-Marie d'Auch when the curators of the Toulouse bridge decided to associate an expert to Dominique Capmartin.
On May 8, 1597, the clerk of the commission noted that arriva en Tholoze Pierre Souffron, Me architecte en la fabrique de l’églize Ste-Marie d’Auch, mandé venir exprès par lesd Sieurs Commissaires pour l’employer à l'œuvre du pont.
On June 3, 1606, "Pierre Souffron, architect of the church of Sainte-Marie d'Aux and builder of the bridge of Saint Subran de Tholoze", made a deal with Messyre Jean de Bessoles, seigneur dudict lieu, Boumont (Beaumont, near Condom), Moissan et autres places.
After his wife's death on August 21, 1642, he remarried in 1646 to Jeanne Galinier, daughter of a painter from Toulouse, and widow of Antoine Pourchet, master apothecary of Saint-Félix-de-Caraman.
On April 3, 1646, he gave his nephew, Jean Souffron, a lawyer at the Bordeaux Parliament, power of attorney to go to the King's Council in Paris to plead his case because he was owed 70000 livres for the materials of the Pont Neuf de Toulouse and obtain an order to pay these sums.