I'm still getting used to exploring the chromosome browser and there are several chromosome matches to my mother-in-law, but fewer with my husband. The match that is the same is on chromosome 21.
After several emails, and inviting each other to view our respective Ancestry.com online trees, we think that her second great-grandmother, Henda Segal Gershman was a sister of my husband's second great-grandfather, Simche Segal/Siegel.
Amazingly enough, although the immigrant Segals settled in Philadelphia and Woodbine, New Jersey, this new-found fourth cousin lives in the town next to ours in Massachusetts. We met for a couple of hours the night before Thanksgiving to share pictures and talk family history. I do see a similarity in some of the Segals in the first couple of generations.
The other helpful thing is that Henda Segal and her husband Louis Gershman had six children (five daughters and a son) and my mother-in-law remembers those sisters who lived in Woodbine; she remembers that they were cousins on the Segal side, but was never clear on exactly how they were cousins. It was a pleasure to confirm for her that those sisters were first cousins to her grandmother, Golda (her photo at right).
I have blogged about Simche Segal's gravestone translation. I also have images of his passenger lists. I blogged about him and his family in census records here and here. I have also shared his 1919 death certificate.
Below is an attempt to graphically display the generations descended from the unknown third great grandparents.
Unknown parents (father possibly Yehuda)
Simche Segal Henda Segal Gershman
Golda Segal Levitt Sadie Gershman Seltzer
Rose Levitt Goldstein Annie Seltzer Walowitz
Mother-in-law New-found 3rd cousin
Husband New-found 4th cousin
Simche Segal's gravestone indicates his father's name is Yehuda; his death certificate indicates his father's name is Israel. (I'm inclined to believe the gravestone.) Henda (Segal) Gershman died in 1909. Her death certificate indicates "unknown" for her father's name. She is buried at Har Nebo Cemetery in Philadelphia and I am looking forward to seeing if the Hebrew on her gravestone can confirm a father's name of Yehuda.