How to generate empty XML element for NULL or non matching values

I have the following query which generates an XML

use tempdb
go

-- Prepare sample data
DECLARE  @Listing  TABLE    (
     ListingID INT,
     Name VARCHAR(200)
    )

DECLARE @Category TABLE (
    ListingID INT,
    CategoryID INT,
    Name varchar(200)
)

INSERT      @Listing
VALUES (1, 'Nike'), (2, 'Pizza hut'),(3, 'Towing Dad'),(4, 'Glorious ManiPedi')


INSERT @Category
values (1,1,'Apparel'),(2,2, 'Pizzeria'),(2,3,'All Restaurants'),(3,4,'Towing')

-- Display the XML
SELECT     
     s.ListingID as [@ListingID],
     s.ListingName as [@ListingName],
    (
        SELECT      x.CategoryID AS [CategoryId],
                    x.Name AS [CategoryName]
        FROM        @Category AS x
        WHERE       x.ListingID = s.ListingID
        FOR XML     PATH('Categories'),
                    TYPE 
     )
FROM  (
        SELECT      ListingID, Name as ListingName
        FROM        @Listing 
        GROUP BY    ListingID, Name
      ) AS s
FOR XML     PATH('Listing'),
            ROOT('Listings');

It generates the following XML:

<Listings>
  <Listing ListingID="1" ListingName="Nike">
    <Categories>
      <CategoryId>1</CategoryId>
      <CategoryName>Apparel</CategoryName>
    </Categories>
  </Listing>
  <Listing ListingID="2" ListingName="Pizza hut">
    <Categories>
      <CategoryId>2</CategoryId>
      <CategoryName>Pizzeria</CategoryName>
    </Categories>
    <Categories>
      <CategoryId>3</CategoryId>
      <CategoryName>All Restaurants</CategoryName>
    </Categories>
  </Listing>
  <Listing ListingID="3" ListingName="Towing Dad">
    <Categories>
      <CategoryId>4</CategoryId>
      <CategoryName>Towing</CategoryName>
    </Categories>
  </Listing>
  <Listing ListingID="4" ListingName="Glorious ManiPedi" />
</Listings>

How can I make the above query generate the following XML:

<Listings>
  <Listing ListingID="1" ListingName="Nike">
    <Categories>
      <CategoryId>1</CategoryId>
      <CategoryName>Apparel</CategoryName>
    </Categories>
  </Listing>
  <Listing ListingID="2" ListingName="Pizza hut">
    <Categories>
      <CategoryId>2</CategoryId>
      <CategoryName>Pizzeria</CategoryName>
    </Categories>
    <Categories>
      <CategoryId>3</CategoryId>
      <CategoryName>All Restaurants</CategoryName>
    </Categories>
  </Listing>
  <Listing ListingID="3" ListingName="Towing Dad">
    <Categories>
      <CategoryId>4</CategoryId>
      <CategoryName>Towing</CategoryName>
    </Categories>
  </Listing>
  <Listing ListingID="4" ListingName="Glorious ManiPedi">
       <Categories>
           <CategoryId />
           <CategoryName />
       </Categories>
  </Listing>
</Listings

Any tips/pointers is appreciated, thanks