I am Vicki Nelson, granddaughter of Vilma Bineth Donner and named for her, she died two months before I was born.
Vilma was a daughter of Karoly Bineth and Betti Grunbaum. I never understood the birth order of their children and grew up not knowing that Karoly had a second wife.
From various pieces of information on Geni and My Heritage it appears that Betti died at the age of 35, perhaps in childbirth. I have documents that show Vilma was born in 1870. It is not possible that there were also two other daughters born in that same year. I assume no one has documentation on their actual birth years. Most of the research on this family has been done by the descendants of Karoly and his second wife.