Cincinnati, Hamilton County, Ohio
Probate Court Archived Records Search Marriage License Index (1817-1983)
John Etzel and Maria (Schumacher) Etzel are both listed in 1854, volume 6, page 635. Married in 1854? Fits with what I know about John Etzel's emigration from Germany to the United States in 1854. Daughter Rose was born in 1855 in Ohio (guessing Cincinnati), which also fits.
Adding to the collection of Etzel sourcing!