I have a bit more information that I got from Lorraine Daros.
William George Juengst and Olga Helmetz had child:
Peter Juengst b. 1815 in Germany
married 1st Margaret. Their kids were:
1. George Juengst born 1829 in Germany, died 1905 in Croton Falls, NY. Married Josephine Rosenberg about 1856. Their kids were:
a. George Juengst b. 8/24/1860, d. after 1925, m.
10/3/1889 to Katherine (Kate) M. Decker b. 1869.
This is your George I think.
b. Magdaline (Lena) Juengst b. 1/1869
c. Augustus A. (Gus) Juengst b. 7/1874
d. Charles A. Juengst b. 1/2/1859 NY, NY, d. 1931
2. Daniel Juengst born 1840 in Kassel Germany possibly
3. Louis Juengst
4. Margarete Juengst
5. Christine Juengst
married 2nd Wilhelmina (Philomena) Wilholm.
1. Charles Juengst born about 1840
2. Henry Juengst born 1846
3. William Juengst born 6/4/1850
I found something on one of your relatives.
Source: Marriage Registers, Extracts from Manhattan (1869-1880) and Brooklyn (1895-1897)
Publisher: Dept. of Health, Division of Vital Statistics, New York.
Publication Place: New York, NY
Marriage ID: 0000028562
Certificate Number: 10882
Name: George Juengst
Spouse Name: Catharine M. M. Decker
Marriage Date: 1888
Marriage Place: Manhattan, New York, New York
1870 census list George Juengst b. 1829 in Germany in Mt. Kisko, NY with Catherine 21, Charles 11, George 10, Magdaline. The kids were born in NY.
I think there is more census information as well
I would love to see how much information you have.