Esther (Netti) Kux was born c. 1848 in Martin, Turocz, Hungary (now Zilina County, Slovakia).
Her parents are unknown.
She married Karol / Carl/ Charles Stein from Vychodna and had children Robert, Wilhelm, Josefine, Etela (Ella), Marta (Martha), Szidonia (Sidi, Sadie), Fani, Amalia (Maly), and three others, names and gender unknown, between 1873 and 1888, and perhaps later.
She died in Martin in 1893.