Here is how this family appears on the 1900 Census:
San Watson head, 24 born Aug 1875; Sallie Watson mother age 60 born 1840; along with Joe Brown age 22 born 1878 and Lizzie Brown age 16 born 1884. Note, the later are labeled as "uncle" and "aunt".
I guess I am trying to figure out how 24-year old San Watson has an uncle Joe Brown age 22 and an aunt Lizzie age 16.
If someone can help me wrap my head around it I will be grateful.