Eta's father's name Leyb appeared in 1858 Revision List. Her maiden surname was Jakobson from Louis & Jacob's wedding certificates. According to Moses in both his wedding certificate and Naturalisation document her maiden name was Yakhis. This was probably Eta's mother's maiden name.
We have no documentary proof that Etta, Leah, and Sarah were sisters but we believe this to be the case. The most famous family story from Hymie Gerber is that his mother Zarra Sussman was a sister to Pesha Leah = Bessie Tankel.