Born to John Ball, tailor of South Molton and his wife, Elizabeth Huxtable, were the following siblings of William Huxtable Ball, 1835-1927:
Ann Huxtable, daughter, baptized 27 Oct 1822, John, son, baptized 24 Jul 1825, and Susanna, daughter, baptized 5 Sep 1830,
according to the Filleigh Baptism Index 1813-1837 on GENUKI.
I was able to find two other daughters: Elizabeth, born ca. 1828, who was named as an exectrix in the will of John Ball Sr., and Louisa Jane, born 1839, who appears with William in the 1841 census.
Research on these individuals and their families continues. When I have more information on them, I will be sure to post.