Question: Is there enough information to call them brothers?

.It would seem rhat they are brothers. As you say, "Celia" is a

good match (ie. a good Anglicized version) for "Ceral" (Yiddish
name Tsir'l). As far as the contention that father's name "Saul"
is not a match for Sasfra, I see no reason why not. If as you say,
the Hebrew names match (both tombstones list father's name as
"Yissachar- that is what matters. Any English name may have been
used in documents to represent the original name. (Both Saul and
Sasfra begin with "S.") Bear in mind that "Sasfra" is highly
suspect as a name. It is probably a corruption of "Socher" a
calique for Yissachar. This explains why Yissachar was rendered
into English using names beginning with the letter "S."

Avrohom Krauss
Telz-Stone Israel