Marie was the daughter of a laundress and a tailor, who came to Paris in the early 1860s from Belgium. She was born in 1865 in the diverse 9th arrondissement of Paris. Marie's oldest sister, Antoinette, was born in Brussels in 1861. A second older sister, also named Marie, died eighteen days after her birth in 1864. Marie's younger sister, Louise Joséphine, born in Paris in 1870, adopted the name of Charlotte and died there in 1945. Her father died at some point between 1870 and 1880, leaving Madame van Goethem to fend for her three daughters on a laundress's income.