Simple FOR XML Explicit query to use on Northwind as a syntax reminder....

select 1 as tag,
   null as Parent,
   null as [TrackSales!1!hide],
   null as [Region!2!RegionName],
   null as [Territory!3!TerritoryName] 
union
select 2 as TAG,
   1 as Parent,
   null as [TrackSales!1!hide],
   rtrim(a.RegionDescription) as [Region!2!RegionName],
   null as [Territory!3!TerritoryName] 
from northwind.dbo.region a inner join northwind.dbo.territories b on a.regionid = b.regionid
union
select 3 as TAG,
   2 as Parent,
   null as [TrackSales!1!hide],
   rtrim(a.RegionDescription) as [Region!2!RegionName],
   rtrim(b.TerritoryDescription) as [Territory!3!TerritoryName] 
from northwind.dbo.region a inner join northwind.dbo.territories b on a.regionid = b.regionid
order by [Region!2!RegionName],[Territory!3!TerritoryName] 
for xml explicit