Very little information has been located about Julia Anna Knox except for her name, and that she was the wife of William Hoisington Goodsell.
Family records ( unsourced except that the information was passed down by relatives), list seven children of the couple. (A photocopy of these notes is uploaded here.)
There was possibly another child named George Duryea Goodsell. (The information about son George comes from http://hoisington-horsington.com/getperson.php?personID=I798&tree=Hoisington). The Hoisington genealogy website linked here (which requires a log-in account) lists only one -- previously unknown -- child of William Hoisington Goodsell and Julia Anna Knox. That child is George Duryea Goodsell, born in 1830, whose parents are William "Hisington" Goodsell and Julia Anna Knox. The source provided at the Hoisington website for this information comes from a book, “The Ely Ancestry: Lineage of Richard Ely of Plymouth, England  *Note: A Findagrave memorial page has been located for a George DAVID Goodsell that lists his parents as Julia Anna Knox and WIlliam Hoisington Goodsell. No source for this information is provided, and the headstone only shows the initial "D" for the middle name. Goodsell-380
One child of the couple who can be found in Iowa County records, is Oliver Hiram Goodsell. He was married on April 4, 1887 in Aplington, Butler County, Iowa. His marriage record lists William Goodsell and Julia Knox as his parents. He was 49 at the time of this marriage, and his estimated year of birth is approximately 1838.
Julia's birthdate is only a guess, based on some of her children's birth dates (1830, 1834, and 1838). On the 1900 census for Moody County, South Dakota, her daughter, Adelia Almira Goodsell listed her mother's birthplace as Pennsylvania. 
According to compiled typewritten notes entitled "The Goodsell Family", by Ella Younker Caul and Edna Bawn Nelsen (descendants), in the possession of R. Greenup, Jullia died when her son Amasa was a baby. Their children are listed as:
There are other children by William's second wife, Clarene Harding that are also listed in the compiled notes. 
Name O H Goodsell Event Type Marriage Event Date 04 Apr 1887 Event Place Aplington, Butler, Iowa, United States Gender Male Age 49 Birth Year (Estimated) 1838 Father's Name Wm Goodsell Mother's Name Julia Knox Spouse's Name Minnie G Babcock Spouse's Gender Female Spouse's Age 22 Spouse's Birth Year (Estimated) 1865 Spouse's Father's Name Hiram Babcock Spouse's Mother's Name Susan Burdis https://familysearch.org/pal:/MM9.1.1/KC49-4LF : 8 March 2016
https://www.ancestry.com/genealogy/records/julia-ann-knox_149538674 A family history lists a Charles Knox and Malonia (probably Mallona) Badger Knox who had a child named Julia Ann Knox, born 19 Sep 1828.
Family of Wm. H. Goodsell, 1840 census, Exeter Twp., Luzerne Co., Penn. (only gender and ages shown, except for Wm. Also shows heads of families of neighbors. "United States Census, 1840," database with images, FamilySearch (https://familysearch.org/ark:/61903/3:1:33S7-9YYV-3GN5?cc=1786457&wc=31SV-JW1%3A1588669737%2C1588670165%2C1588669165 : 24 August 2015), Pennsylvania > Luzerne > Exeter Township > image 19 of 26; citing NARA microfilm publication M704, (Washington D.C.: National Archives and Records Administration, n.d.). https://www.familysearch.org/ark:/61903/3:1:33S7-9YYV-3GN5?i=18&cc=1786457
Have you taken a DNA test for genealogy? If so, login to add it. If not, see our friends at Ancestry DNA.
On 17 Nov 2018 at 13:32 GMT Phillip Rich wrote:
This implies to me that Julia Anna was still living at the time of the 1840 census and had 6 living children 3 boys & 3 girls. William's 2nd wife Clarissa would have been too young to be listed as 20-30.
All considered, I would place her DOB between 1811 & 1817 and her DOD between 1840 & 1843
Julia is 19 degrees from Robin Helstrom, 23 degrees from Katy Jurado and 18 degrees from Victoria of the United Kingdom of Great Britain and Ireland on our single family tree. Login to find your connection.