Emile and his two brothers, Francois and Florimond, were talented artists and each spent some time at the Gobelins. At the factory Abel Lucas trained Marnier as a draughtsman and he developed a close relationship with Lucas and his family, eventually marrying Lucas daughter, Henriette, in 1861. In 1867, Henriette gave birth to a son, Emile Henri. Six weeks after the birth, having contracted severe rheumatism, Henriette died prematurely.
Sargine Augrand, a student of Lucas and a close friend of Emile and Henriette (before she died), caught Emile’s eye; they married in 1872 and lived in a small apartment and studio. The couple had one child, a daughter, Marie-Louise, born in 1874.