There are two men named Frederick Slates in Carroll County, Ohio of about the same age at the same time.
One is the son of Frederick and Rebecca Knee Slates and was living in Perry Township, Carroll County, Ohio and according to his wife's obituary had lived there his entire life, including found in the 1850 census in the household of his father, Frederick Slates. That Frederick b. 1818 married a woman named Susanna Smith on 27 May 1851 and appears to have died the same year 1908 and can be found in Arabia Cemetery. His father Frederick, is the brother of this memorial's father.
This Frederick was living in Loudon Township, Carroll County, Ohio in 1850 with this wife Susanna Hilbert whom he married 19 Dec 1848 and their daughter Elizabeth born 1850.
From a biography of Amos Slates the son of Adam Slates who is the son of John Slates and brother of Frederick Slates of this memorial:
"John Slates, grandfather of our subject, was born in Loudoun County, Virginia August 2, 1784 and was married April 10, 1807 to Miss Elizabeth Ruse, also a native of Loudoun county, the union resulting in the birth of seven children, viz: Mrs. Catherine Albaugh, Mrs. Elizabeth Shanover, Mrs. Margaret Woods, Mrs. Mary Richey, Adam, John and Frederick Slates."
Portrait and Biographical Record of Mercer and Van Wert Counties, Ohio;
Bowen & Co., 1896, p.692
Family Members
Parents
John Slates
1784–1859
Elizabeth Ruse Slates
1780–1855
Spouse
Susanna Hilbert Slates
1830–1903
Siblings
Catherine Shearer Slates Albaugh
1812–1884
Elizabeth Slates Shawver
1813–1887
Margaret Slates Wood
1817–1888
Adam Slates
1818–1852
Mary Slates Ritchie
1820–1863
John W. Slates
1821–1905
Children
Mary Elvira Slates Miller
1850–1931
Elizabeth Ann Slates Burrier
1851–1921
Franklin Pierce Slates
1852–1934
Uriah Parkinson Slates
1854–1931
Peter Slates
1855–1935
Oscar Benton Slates
1857–1909
John William Slates
1859–1927
Parley Hilbert Slates
1866–1949
Minerva Ellen Slates Margrat
1872–1956
