I have found a bit more information regarding siblings, previously unknown, of Jacob.
Marie - born abt. 1845 married Johann Hamernik in 1863, three children that I know of.
Anna - born abt. 1846 married Josefa Koranda abt. 1873, three children.
Terezie - born 1852, no further information
Frantisek - born 1866 married Majdaleny Janna, date unk., five children.
I still don't know, at this time, if Jacob's father (Kaspar) had any siblings, so I can't link definitely to any of the previous posts.
I do have a copy of the genealogy work compiled by Mary (Divoky) Lampman.