def childRecords(self):
        """
        Returns a record set of children for this item based on the record.  If
        no record set is manually set for this instance, then it will use the
        hierarchyColumn value from the tree widget with this record.  If no
        hierarchyColumn is speified, then a blank record set is returned.
        
        :return     <orb.RecordSet>
        """
        if self._childRecords is not None:
            return self._childRecords
        
        tree = self.treeWidget()
        try:
            table, column = tree.hierarchyLookup(self.record())
        except AttributeError:
            table = None
            column = ''
        
        # returns the children for this information
        if table and column:
            return table.select(where=Q(column) == self.record())
        
        # returns a blank record set if no other records can be found
        return RecordSet()