Searching for information: Regina Kiesler and Nathan Byk

Hi Everyone –  Greetings from Chicago.   I’ve been reading all of your emails,  and this is the first time I’ve posted.
My Great, great Grandfather and GGGM were from Czernowitz.   I cannot locate any birth certificates or birth info on either of them.   They moved to Vienna at some point where they both are buried in the Zentralfriedhof Cemetery.
From the obituaries below I’m hoping one of you may recognize them,  their children etc.   One of Nathan’s sons is Alexander Byk,  my  GGGrandfather.  He was born in Bojan,  Bukovina, in June, 1869 and was married in Brody.   He also moved to Vienna with his wife Friedericke Debora Byk (b.  1870).   Not sure if Nathan and Regina moved to Czernowitz after that but I’m stuck as far as genealogy goes.   Thanks for your help
Hetty Schimmel-Lima <halrph@sbcglobal.net>
Obituary of Nathan Byk (d. Vienna, 1916)

Obituary of Nathan Byk (d. Vienna, 1916)

Obituary of Regina Byk (born Kiesler)

Obituary of Regina Byk (born Kiesler)