Angela,

On the the 1880 census film, the "Relationship to Head of Household" field is blank for all of the persons listed with Dutch and Leni Loggins except for Cal McCustian who is listed as a boarder. In the transcribed version of the 1880 census at familysearch.org, Emma is listed as a sister but on the film, the field is blank just like the other children. From what I can see, there is no reason to believe that these are not all (including Emma) the children of Dutch and Leni Loggins.

Ron