Below is an image of a query that will get you all registered families based on organization information. This will give you the count of all registered families that are at that organization with Organization ID, Organization Name and City of the Organization.
I have renamed the columns on the right-hand side in order for the results columns to read easier. In order for this query to work, you will need to do a 'count' of the family DUID. If you do a 'Sum' then it will literally add together each family DUID, so do a 'Count' and not a 'Sum'.