Hi, I have the Gnadenhutten Cemetery Book. There are Gross's there but no Abraham,

Robert B- 1880-1926
Anna J.- 1862-1930
B. Frank- 1847-1933
Benedict M. -1 Jan 1851-11 Oct 1861, buried at beersheba
Charles Willis- 5 Apr 1862-8 May 1864, buried Beersheba
Benedict M. 27 Feb 1818- 4 Feb 1909
Malinda, w/B.M.- 19 Dec 1823-12 Mar 1910

Not sure if any of this helps but that is what is in Gnadenhutten.
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