In view of her later opinions, it is interesting to remember that Sibylle was actually descended from Octave Mirabeau's royalist younger brother, André-Boniface-Louis de Riquetti, vicomte de Mirabeau, (1754–1792) known as Mirabeau-Tonneau because of his notorious embonpoint, who famously broke his sword in front of France's Revolutionary Assembly (where he represented the nobility of the Limousin) while bitterly crying out: "now that The King is giving up his kingdom, a nobleman no longer needs a sword to fight for him!"

At her father's request, the name on her birth certificate was revised to read "Sibylle Aimée Marie Antoinette Gabrielle".

Gyp wrote humorous sketches and novels which brazenly denounced her own fashionable society as well as the French republic's political class.

Starting in 1880, she began to publish in book form, under the pseudonym of Gyp, a total of more than 120 works, many highly successful: Petit Bob, (1882), Les Chasseurs, Un trio turbulent, Autour du mariage (1883), Ce que femme veut (1883), Sans voiles (1885), Autour du divorce (1886), Dans le train (1886), Mademoiselle Loulou (1888), Bob au salon (1889), L'éducation d'un prince (1890), Passionette (1891), Oh!

Her best-known work is probably Le Mariage de Chiffon, filmed in 1942 by Claude Autant-Lara.