Mendel Gottesman - Marriages, plus which children are by first wife

Mendel = Mendel Gottesman
was married to two wives

The first was Cili Gottesman
The record of that marriage can be found on JewishGen in the Subcarpathia Jewish Marriages
GOTTESMAN Mendel -- Age 27 - single - ..- Father: Samuel -- Mother: SPIGLMAN Chaje
FUCHS Cili - Age 17 - single - ...- Father: Jakob -- Mother: SPIELMAN Feige
Marriage Date: 28-JAN-1879 -- Marriage Town: Munkacs (original name) - Mukacheve (modern name)

On the 1900 Census, "Sarrah" is labelled "wife #II" and they have been married 9 years. So that would mean married about 1891.
He immigrated in 1888, she immigrated in 1884. I have not yet found their marriage record, but they were married after coming to the US.