Can't bind child collection in silverlight - silverlight

Question

I have a pretty simple setup that I cannot get to work in silverlight. I have an order with a collection of OrderPayments. These objects are part of a Entity Framework model and are exposed through WCF RIA Services. I can bind perfectly fine to any basic property on the Order class, but I wanted to bind to a listbox to show the OrderPayments. Here's the XAML for the ListBox.
<ListBox ItemsSource="{Binding Data.OrderPayments, ElementName=orderDataSource}"></ListBox>
Nothing ever appears in the listbox and there is at least one OrderPayment for the order displayed. orderDataSource is a DomainDataSource that contains the Order. The odd thing about this is that I don't receive any binding errors and when I bind to a TextBlock using the following code:
<TextBlock Text="{Binding Data.OrderPayments, ElementName=orderDataSource}" />
The text 'OrderPayment' is outputted to the screen. Is there something different I have to do to get Silverlight to actually pick up the reference to the object?
Entire XAML below:
<riaControls:DomainDataSource AutoLoad="True" Name="orderDataSource" QueryName="GetOrder">
<riaControls:DomainDataSource.QueryParameters>
<riaControls:Parameter ParameterName="orderid" Value="1" />
</riaControls:DomainDataSource.QueryParameters>
<riaControls:DomainDataSource.DomainContext>
<ds:CEWCPSDomainContext />
</riaControls:DomainDataSource.DomainContext>
</riaControls:DomainDataSource>
<StackPanel Orientation="Vertical" Margin="12">
<StackPanel Orientation="Horizontal">
<Button Width="100" Height="50" Content="Save & Return" Margin="0,0,12,12" />
<Button Width="100" Height="50" Content="Orders" Margin="0,0,12,12" />
<Button Width="100" Height="50" Content="Emails" Margin="0,0,12,12" />
</StackPanel>
<StackPanel Orientation="Horizontal">
<dataForm:DataForm x:Name="dataForm1" Header="Order Contact Information"
AutoGenerateFields="False" AutoEdit="False" AutoCommit="False"
CurrentItem="{Binding Data, ElementName=orderDataSource}">
<dataForm:DataForm.EditTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<StackPanel>
<dataForm:DataField Label="First Name">
<TextBox Text="{Binding FirstName, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }" />
</dataForm:DataField>
<dataForm:DataField Label="Last Name">
<TextBox Text="{Binding LastName, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField Label="Organization">
<TextBox Text="{Binding Organization, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField Label="Phone">
<TextBox Text="{Binding Phone, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField Label="Fax">
<TextBox Text="{Binding Fax, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField Label="Email">
<TextBox Text="{Binding Email, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField Label="Address 1">
<TextBox Text="{Binding Address1, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField Label="Address 2">
<TextBox Text="{Binding Address2, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField Label="City">
<TextBox Text="{Binding City, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField Label="State">
<TextBox Text="{Binding State, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<StackPanel Orientation="Horizontal" Width="Auto">
<dataForm:DataField Label="Zip code">
<TextBox Text="{Binding Zip, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
<dataForm:DataField>
<TextBox Text="{Binding Zip4, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
</StackPanel>
<dataForm:DataField Label="Country">
<TextBox Text="{Binding Country, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True }"/>
</dataForm:DataField>
</StackPanel>
</StackPanel>
</DataTemplate>
</dataForm:DataForm.EditTemplate>
</dataForm:DataForm>
<StackPanel Orientation="Vertical">
<TextBlock FontWeight="Bold" FontSize="16" Text="Order Total / Payments" />
<TextBlock >
<Run Text="Order Total:" />
<Run Text="{Binding Data.OrderTotal, ElementName=orderDataSource}" />
</TextBlock>
<TextBlock Text="Payments" />
<TextBlock Text="{Binding Data.OrderPaymentItems, ElementName=orderDataSource}" />
<ListBox ItemsSource="{Binding Data.OrderPayments, ElementName=orderDataSource}">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Amount}" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</StackPanel>
</StackPanel>

Answer 1

WCF RIA Services does not include child entities by default. I needed to put [Include()] on the OrderPayments property of the Order object. Works like a charm now.