ACS: Identifying parents of grandchildren in a munti-generations household

If head of household has children and grandchildren in the household, is it possible to tell which of the children is/are the parent/s of any given grandchild?

Yes, this is possible using some of the family interrelationship variables available. One way in which you approach this question is to use RELATE==09 to find grandchildren of the head of the household. You can then reference MOMLOC and POPLOC to find that grandchild’s mother/father location in the household if present.