Understanding Society User Support

I could be misunderstanding the data and coding, but it would appear to me as if some of the relationship data is not consistent. For example, household number 68028563 contains six individuals at Wave 1. It would appear that person 2 is the husband/spouse of person 1 and that persons 3 through 6 are the natural parent of person 1. Is it to be assumed that that two of these are parents-in-law (i.e. code 13 instead of 9)? Further, within this household, persons 3 through 6 identify persons 1 and 2 as natural son/daughter, and the (other) persons 3 through 6 as natural brother/sister. That is, person 3 identifies persons 4, 5 and 6 as natural brother/sister. Would it be possible to get some feedback on this?