At Connecting with a Handler Cousin, I shared the link to a 1988 video interview that my husband's second cousin did with his aunts, my father-in-law's cousins Esther and Helen Solomon.
At about 18:45 minutes in, the sisters start talking about their mother's father, Aaron Handler. Their mother's name was Regina (younger sister to Sam and Joseph Handler). According to Helen, her grandfather, Aaron Handler, was a wealthy farmer who owned a large farm. He had four sons with his first wife, whose name they don't know. The sisters share a little bit of what they remember of these older sons of Aaron (Herman, Leopold, Philip, and "the one who made his career in the service").
After taking a brief break, the video interview continues and it comes out that after Aaron's first wife died, he married his brother's daughter: his niece, whose name is Sarah Handler, as remembered by Helen and Esther. They don't know Sarah's father's name.
I have written about this great-grandmother of my husband's before at: Finding A Jewish Great Grandmother (which includes her death certificate) and Great-Grandmother Handler Married Twice. And at one of my favorite blog posts: Passenger Lists...And Following Up on Family Stories.
JewishGen's JOWBR (JewishGen Online Worldwide Burial Registry) has a record for Sally Handler, buried in Lansing Avenue Cemetery in Cleveland, Ohio. With some additional digging, I found that she is buried in row 15 of the Knesseth Israel section of the cemetery and I'm hoping someone will fulfill the FindAGrave photo request I have made.
JewishGen has this cemetery in its index and the record for "Sally Handler" indicates that her tombstone reads: "Chaya Sara bat Zvi."
If this is correct (and I'd love to see the tombstone to be sure), then Zvi Handler is brother of Aaron Handler and father of Sarah / Sally Handler.
Another interesting thing to think about: In looking up the given name Zvi at JewishGen's Given Names Database (for Hungary), the U.S. equivalent is Herman or Harry.