The German words Bruder und Schwester are inscribed on the front of this marker, located in row 3 of Zion Lutheran Cemetery, Chattanooga, Ohio.
Brother and Sister.
The column portion of this tombstone is now leaning against its base. It is a little difficult to see, but the base behind the column bears the name Kuhm in large letters.
At first I glance, looking at only the front of the tombstone, I thought it was probably the marker of two young siblings. But that is not the case. There is writing on two other sides of the marker that tell who the brother and sister were. Those inscriptions on the sides could easily be missed.
The north side of the marker is inscribed:
26 Oct 1899
28J 10M 1T
Off. 1-11, Joh. 21:4
[Georg Kuhm died 26 Oct 1899, age 28 years, 10 months, 1 day.]
The south side of the marker is inscribed:
3 Apr 1909
41J 8M 17T
1 Cor. 15: 42-43
[Lena Kuhm died 3 April 1909, age 41 years, 8 months, 17 days.]
They were not young children at all. Who were these two siblings, from a family that I know very little about? The only thing I know about the Kuhms is that is that there is a Miller/Kuhm marriage in the family. Pete Miller married Della Kuhm about 1914. Pete was the son of Jacob Miller [my great-grandfather] and his second wife Margaretha Strable. Pete was my granduncle and Della was the daughter of Michael Kuhm Jr and Maria Geier.
I found very little information about the Kuhm brother and sister in my two favorite Internet go-to sites, Ancestry.com and FamilySearch.org. So I went to one of my favorite and best local resources, Zion Chatt’s church records, where the family is mentioned a few times. 
The Kuhm family first appears in Zion’s records in 1875, when Michael Kuhm and his wife Elisabeth were baptismal sponsors for Elisabeth Hiller. There are a few Kuhm marriages, confirmations, and burials in Zion’s records. From these entries I learned that Elisabeth’s maiden name was Müller. That several, if not all, of Michael and Elisabeth’s children were born in Schillersdorf, Elsass, in what is now Germany. And that they immigrated sometime after 1863 and eventually lived in Jefferson Township, Adams County, Indiana.
Georg Kuhm, the brother named on the tombstone, was confirmed 6 April 1884 at Zion. This record gives his date of birth as 16 December 1871 and named his parents as Michael and Elisabeth Kuhm. He was likely born in Germany. Zion’s records indicate that he died in Hamilton County, Ohio, of a brain inflammation and stroke. He was survived by his widow, 2 children, his parents, and 6 siblings. The church burial record shows his age as 27 years, 10 months, and 10 days, which agrees with the 16 December birth date, but which disagrees with his tombstone inscription.
I did find a couple records for Georg Kuhm on Family Search and they add to the above information. Georg married Lizzie Goess in 1894 in Butler County, Ohio.  They had at least one son, Albert, born 12 April 1897, in Hanover Township, Butler County.  This would correspond with his death/burial information in the church records which states he was survived by a wife and 2 children and he died in Hamilton County, which is near Butler County. He was probably brought to his family and former home near Mercer County to be buried.
According to Zion’s records, his sister Magdalena “Lena” Kuhm was confirmed 16 April 1882. She died of pneumonia on 3 April 1909, at the age of 41 years, 8 months and 16 days and was buried on the 6th. Her calculated date of birth is 18 July 1867. Although the church records do not specifically name her parents, she communed with Michael and Elisabeth, the only Kuhm family in the area, and most importantly, her tombstone indicates she was the sister of Georg, who we know was the son of Michael and Elizabeth.
From the church records I was able to determine most of Georg and Lena’s siblings:
Maria Kuhm, married Georg Berron
Michael Kuhm Jr, married Maria Geier
Jacob Kuhm (1863-1899),married Julie Berron
Margaretha Kuhm, married Michael Schott
Bruder and Schwester.
 I have seen this name spelled Kuehm and Kühm, and our family usually pronounces the name as Keem, with a long e.
 “Ohio, County Marriages, 1789-1997,” index and images, FamilySearch (www.familysearch.org : accessed 20 Jul 2014), George Kuehm and Lizzie Goess, 4 Feb 1894; citing Marriage Records 1890-1898, Vol. 6, p. 229, Butler County, Ohio; from FHL microfilm 355780.
 “Ohio, County Births, 1841-2003,” index and images, FamilySearch (www.familysearch.org : accessed 20 Jul 2014), Albert Kuehm, 12 Apr 1897; citing Butler County, Ohio, Births, Vol. 3, p. 142-3; from FHL microfilm 373049.