Thus far I found in the 1920 census a Ben(jamin?) Carl Stern, b. 1900 in Austro-Hungary, who was a shipping clerk for "underwear." His sister Bertha designed underwear and his sister Florence was an underwear saleswoman. A 1924 classified ad from the Flobert Co. (named, I assume, for Ben's sisters Florence and Bertha) of 30 E. 33rd St in NYC solicited a presser for "high-class silk underwear." In the 1930 census Ben C. Stern was a salesman for lingerie and his 1940 WWII draft registration noted he was employed by Flobert Co of 146 Madison Avenue in NYC. A 1941 ad for The Flobert Co. noted the company was the "Maker of women's ultra fashionable year round negligees, pajamas, robes, lounge wear."
The 1957 Greater NY Industrial Directory recorded the following officers of Flobert Co., Inc of 146 Madison Avenue, NYC: President Ben C Stern and treasurer Samuel Stern. The Flobert Co. products were housecoats and negligees. The 1958 Industrial Directory of New York State noted the Flobert Co., Inc. sold/produced?/manufactured? women's housecoats, negligees, and lounging pajamas and the president Ben C Stern was assisted by treasurer Samuel Stern.
A 1967 newspaper article reported the engagement of Patricia Stern, daughter of Ben C. Stern, president of Flobert Co. of New York City, and his wife. A 1968 Who's Who publication reported Stanley J. Stein was a partner in Flobert Co.
I will look for a bit more information in a day or two.