After a short search, here is some basic information:
Fern E. Wentzel b. approx. May 1918.Her brother is Bruce G. Wentzel, b. approx 1924.
1930 census, Muhlenberg Twp, Berks Co., PA:Residing at 203 Raymond St. is Obidiah R. Reeser, Head of family and wife Elizabeth G. Reeser, have adopted as daughter, Minerva A. Wentzel.Minerva is married, not divorced, or widowed, but her husband Bernard G. is not enumerated with the family.Since Minerva is adopted, her children Fern & Bruce are listed as grandchildren to Obidiah Reeser.
1920 census, Muhlenberg Twp., Berks, PA:203 Raymond St. Obediah R. Reeser, 57yrs; Elizabeth G. wife,53yrs; Bernard G. Wentzel, boarder 24yrs; Minerva A. Wentzel, niece,28yrs; Fern Elizabeth, grandniece, 1 8/12 yrs.
1910 census 14th ward, Reading, Berks Co., PA:Andrew S. Wentzel head, Emma G. wife, several sons, including Aaron C. b. 1889 & Bernard G. b. 1894. ALSO,Emma Pennypacker, 10 yrs. granddaughter & Louis B. Pennypacker, 5 yrs, grandson.
1900 census Muhlenberg Twp., Berks, PA: Andrew S. Wentzel b. May 1853 head, Emma G. b. Oct 1855 wife, & married in 1875.Andrew S. b. June 1881 son, Harry F. b. Aug 1883 son, Daniel J. b. Feb 1886 son, Leo C. b. July 1890 son, Bernard G. b. Jan 1894 son,John C. b. July 1897 son. (There is another son enumerated in 1910 Aaron C. b. 1889) This family is enumerated next to Aaron Wentzel(b. 1827) and wife Catharine (b. 1829) Wentzel.Most likely Andrew S.'s parents.(notice the connection of the first name Aaron)
1880 census:Andrew S. & Emma G.Wentzel have 2 daughters, Katie b. 1876 and Mary b. 1878. Since Andrew S. & Emma married in 1875, it makes sense that they would have a child a year later, which was common. Either the daughters died before 1900, or married and are enumerated under a married name.(Check out the Pennypacker surname)
This is just a scratch on the surface, as it appears there are many siblings to this family.Hope this helps.