1st ensure you only have one family reference per union by opening unions table layout and sorting on references. Edit any union showing more than 1 reference via the associated family records and add a unique comment so that a new union is cloned for that family. Continue until all unions only have one family reference i.e. no 'shared' unions. With the Unions table sorted on the References column copy the 'union place' column. Now switch to the families table view and sort on Unions column to achieve the same order. Now paste the copied column into a spare custom tag column. You can now sort the family table by 'union place' by sorting on this custom tag column. You can then remove any unique comment added to unions and later clear the custom tag column.