How to use left over space in wpf tab items row

Question

Upper part of TabControl consists of TabItem controls. Is there a way to reuse remaining space there to put some WPF content?

I think I could use a "fake" TabItem with different styling and put my stuff in TabItem.Header but I was hoping there's a better way.

Solution

Based on the answer below, I got the desired behavior by wrapping TabPanel in the template below within e.g. StackPanel and adding my additional content after it.

<StackPanel Orientation="Horizontal">
   <TabPanel 
    Grid.Row="0"
    Panel.ZIndex="1" 
    Margin="0,0,4,-1" 
    IsItemsHost="True"
    Background="Transparent" />
    <TextBlock>Foo</TextBlock>
</StackPanel>

Answer 1

You can use a template and make it do whatever you want, that is the power of WPF. Here is a nice article on customizing the TabControl and the TabItem controls.

< EDIT Adding code for TabControl template from Switch On The Code article>

<Style  TargetType="{x:Type TabControl}">
  <Setter Property="Template">
    <Setter.Value>
      <ControlTemplate TargetType="{x:Type TabControl}">
        <Grid>
          <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
          </Grid.RowDefinitions>
          <TabPanel 
             Grid.Row="0"
             Panel.ZIndex="1" 
             Margin="0,0,4,-1" 
             IsItemsHost="True"
             Background="Transparent" />
          <Border 
             Grid.Row="1"
             BorderBrush="Black" 
             BorderThickness="1" 
             CornerRadius="0, 12, 12, 12" >
            <Border.Background>
              <LinearGradientBrush>
                <GradientStop Color="LightBlue" Offset="0" />
                <GradientStop Color="White" Offset="1" />
              </LinearGradientBrush>
            </Border.Background>
            <ContentPresenter ContentSource="SelectedContent" />
          </Border>
        </Grid>
      </ControlTemplate>
    </Setter.Value>
  </Setter>
</Style>

all you have to do is add your content to the Template, the part that holds the tab items is the <TabControl>