Avraham Aharon Fine - Children

What connects all the children to each other? To these parents?

Both Dora Fine and Jenny Korman are buried in the Riga Kurlander Verein Cemetery in Baltimore.
The info shown for their father Avraham does not suggest any connection to Riga.

Moreover, Jenny's gravestone has her father as [Avraham] and Dora's has him as [Avram Yitzhak]
These might well refer to the same person, and since Dora's obit clearly says they are sisters I assume they do -- but what connects them to someone named Avraham Aharon?

Osher Fine has a Photo of a Marriage Record from JewishGen/LitvakSig.
The Record can be found in Lithuania Marriages and Divorces.
The Groom is FAINAS / [FAIN], Osheris / Osher -- Parents: Abramas / Abram and BURGINAITE / [BURGIN], Reize.
That certainly seems to tie Osher to the couple shown as his parents.

There is a Page of Testimony https://yvng.yadvashem.org/nameDetails.html?language=en&itemId=... for Motel Fein, father Avraham Aharon and Mother Reizl - Spouse's Maiden Name: Khana Salanski -- submitter Avraham Fein, his son.
So that seems to document Mordechai Motel Fine

But despite the fact Avraham Fein seems to have submitted Pages of Testimony for over two dozen different individuals, I am not seeing any submissions from him for any siblings of his father.

Where did info on the rest of the children come from?