I do not have any information on William J. HAMMAN.
I have a John HAMMAN (b. 1840) but he is not a sibling of Fred, George and Mary.
I do have information on Fred, George and Mary.They are part of my gg grandmother's family.What information I have so far is as follows (most all of it donated from other generous HAMMAN(N) researchers):
Heinrich HAMMANN (b. 09 Sep. 1807 in Lachen, Neustadt, Bavaria; d. 1876, prob. in Pike Co., OH or Morgan Co., IL) married: Barbara REYBERT (b. 1815; d. 1882 in Morgan Co., IL)
Their children were:
1) George Henry HAMMAN (b. 12 Sep. 1840, Seal Twp., Pike, OH; d. 01 Feb. 1913, Meredosia, Morgan, IL)
2) Elizabeth HAMMAN (b. 22 Dec. 1842, Seal Twp, Pike, OH; d. 16 Jul. 1924, Arenzville, Cass, IL)
3) Andrew HAMMAN (b. 1846, Seal Twp., Pike, OH; d. 1915, Meredosia, Morgan, IL) and twin 4) Frederick HAMMAN (b. 1846, Seal Twp., Pike, OH; d. 1933, Meredosia, Morgan, IL)
5) Mary HAMMAN (b. 1849)
Child #2 above is my gg grandmother.She married John Adam ZAHN (b. 25 Aug. 1842, Seal Twp., Pike, OH; d. 26 Jul. 1871, Cass Co., IL) on 06 Oct. 1864 in Seal Twp., Pike, OH.They had three children: Dora, Edward and Emma.
I have information on other HAMMAN(N)s if you would like it.Just let me know.