When John Henry Helmlinger was born on November 20, 1891, his father, Jacob, was 31 and his mother, Magdalana, was 27. He had two brothers and three sisters. He registered for the draft on 5 June 1917, at which time he was single and working as a saw miller.
He entered the Army (not certain if he enlisted or was drafted) on 25 April 1918 in Sidney, Ohio. The following information comes from "The official roster of Ohio soldiers, sailors and marines in the world war, 1917-18" compiled by the state of Ohio based on military service records (bracketed words/phrases are replacements of abbreviations):
"Helmlinger, John H., 2426589, White, R.F.D. 2, Jackson Center, [Ohio]
[National Army] Sidney, [Ohio] Apr 25 [1918]. [Born] Jackson Center, [Ohio]. 26 5/12 yrs. 16 [Company] 4 [Training Battalion] 158 [Depot Brigade] to May 3 [1918]; [Company] H 330 [Infantry] to Aug 1 [1918]; [Company] D 16 [Infantry] to death. [Private] St Mihiel; Meuse-Argonne; Defensive Sector. [American Expeditionary Forces] June 12 [1918] to death. [Died of Wounds] Oct 19 [1918]. Notified Mrs. Magdalena Helmlinger, mother, R.F.D. 2, Jackson Center, [Ohio]. Cited in [General Order] 1 [Division] dated Jan 1 [1920]."
Source of information: www.findagrave.com, www.ancestry.com