David,
Not quite sure what your requirements are, however in a previous project I needed to register families/households and identify their children living in each, and as then recruit and register the all the children to be the actual subjects of the study.
So for the recruitment and study management we had the household and head of household as our subjects of interest and for the study phase the children were the subjects of interest.
This was achieved by creating two separate but related related redcap projects - Households and Children
Once the parents consented, we created a record for each the children in the household project (via a repeating form) and when these forms when save would generated a unique URL in the format that REDcap would execute to generated the Childs record in the children project (where all the recurring study instruments were located). The URL contained data about the household ID, so we could generate an ID for the child that linked them to their household.
That way we could have as many children as needed for each family (like a repeating form) and seperate cleanly the data for recruitment, household and research management, and the data for the children (who were the subjects of the study) while maintaining the relational link between children and families for analysis and achieving a minimum of data duplication and reentry
The research assistants were local community people using REDcap on mobile devices so the whole thing had to be simple to use, workflow driven and with with a minimum of cognitive load and processing on the data collectors.
Happy to discuss further, however it was a complex solution but meant we could use REDcap for both recruitment and study phases and eliminate need for excel spreadsheets and other project management tools - it was all in one place for the project manager
Peter Macisaac