How can I "Click Through" a control in WPF?

Question

I have an order entry form that has a ListBox with a list of line items. I have my items template, and one of the values is a ComboBox in each of my Items.

Now, my form can also create Credit memo's in addition to purchase orders, but when I am creating a credit memo, I want to put the words "Credit Memo" over the list box, however, the TextBlock covers the ComboBox in two of my line items. I would like to pass my click event through the TextBlock to the ComboBoxes but I'm not sure how to do it.

This is what I have, ( Maybe I am coming at this totally wrong, I am kinda a noob with WPF )

<ListBox SelectionMode="Single" Grid.Row="2"           ItemsSource="{Binding Path=LineItems}" HorizontalContentAlignment="Stretch"           IsSynchronizedWithCurrentItem="True" Background="#66FFFFFF">     <ListBox.ItemContainerStyle>         <Style TargetType="{x:Type ListBoxItem}">             <Setter Property="Background" Value="WhiteSmoke"/>             <Setter Property="BorderThickness" Value="1" />             <Style.Triggers>                 <DataTrigger Binding="{Binding Path=IsPartBackOrder}" Value="True">                     <Setter Property="Background" Value="Orange" />                 </DataTrigger>                                    </Style.Triggers>         </Style>     </ListBox.ItemContainerStyle>     <ListBox.ItemTemplate>         <DataTemplate DataType="{x:Type Entities:SalesOrderLineItem}" >             <OrderEntry:SalesOrderLineItemCreate DataContext="{Binding}" DeleteSalesOrderLineItem="DeleteSalesOrderLineItem" Margin="0,3,3,0" >                 <OrderEntry:SalesOrderLineItemCreate.Resources>                     <Style TargetType="{x:Type OrderEntry:SalesOrderLineItemCreate}">                         <Style.Triggers>                             <DataTrigger                                      Binding="{Binding RelativeSource=                                       {                                          RelativeSource                                           Mode=FindAncestor,                                           AncestorType={x:Type ListBoxItem}                                       },                                        Path=IsSelected                                      }" Value="True">                                 <Setter Property="Background" Value="LightBlue" />                                 <Setter Property="Foreground" Value="Black" />                             </DataTrigger>                         </Style.Triggers>                     </Style>                 </OrderEntry:SalesOrderLineItemCreate.Resources>             </OrderEntry:SalesOrderLineItemCreate>         </DataTemplate>     </ListBox.ItemTemplate> </ListBox>  <TextBlock Grid.Row="2"             Text="Credit Memo"             HorizontalAlignment="Center"            VerticalAlignment="Center"            FontSize="48" Height="Auto"            FontStyle="Italic"            Foreground="Red"            Opacity=".25">     <TextBlock.Style>         <Style TargetType="{x:Type TextBlock}">             <Style.Triggers>                 <DataTrigger Binding="{Binding Path=OrderType}" Value="CR">                     <Setter Property="Visibility" Value="Visible" />                 </DataTrigger>                 <DataTrigger Binding="{Binding Path=OrderType}" Value="CU">                     <Setter Property="Visibility" Value="Hidden" />                 </DataTrigger>             </Style.Triggers>         </Style>     </TextBlock.Style> </TextBlock> 

Answer 1

<TextBlock IsHitTestVisible="False" .../>