Как изменить семейство шрифтов в ContentPresenter?

У меня есть собственный шаблон для расширителя, который близок к приведенному ниже коду. Мне пришлось изменить часть кода, чтобы убрать пользовательские классы, кисти и т. д.

<Style TargetType = "{x:Type Expander}">
  <Setter Property = "HorizontalContentAlignment"
          Value = "Stretch" />
  <Setter Property = "VerticalContentAlignment"
          Value = "Top" />
  <Setter Property = "BorderBrush"
          Value = "Transparent" />
  <Setter Property = "FontFamily"
          Value = "Tahoma" />
  <Setter Property = "FontSize"
          Value = "12" />
  <Setter Property = "Foreground"
          Value = "Black" />
  <Setter Property = "BorderThickness"
          Value = "1" />
  <Setter Property = "Margin"
          Value = "2,0,0,0" />
  <Setter Property = "Template">
    <Setter.Value>
      <ControlTemplate TargetType = "{x:Type Expander}">
        <Border x:Name = "Border"
                SnapsToDevicePixels = "true"
                Background = "White"
                BorderBrush = "{TemplateBinding BorderBrush}"
                BorderThickness = "{TemplateBinding BorderThickness}"
                Margin = "0,0,0,10"
                Padding = "0"
                CornerRadius = "8">
          <DockPanel>
            <Border x:Name = "HeaderSite"
                    Background = "Blue"
                    CornerRadius = "8"
                    Height = "32"
                    DockPanel.Dock = "Top">
              <DockPanel>
                <ToggleButton Foreground = "White"
                              HorizontalContentAlignment = "{TemplateBinding HorizontalContentAlignment}"
                              VerticalContentAlignment = "{TemplateBinding VerticalContentAlignment}"
                              Margin = "0"
                              MinHeight = "0"
                              MinWidth = "0"
                              Padding = "6,2,6,2"
                              IsChecked = "{Binding Path=IsExpanded, Mode=TwoWay, RelativeSource = {RelativeSource TemplatedParent}}"
                              DockPanel.Dock = "Left">
                </ToggleButton>                

                <ContentPresenter SnapsToDevicePixels = "True"
                                  HorizontalAlignment = "Left"
                                  Margin = "4,0,0,0"
                                  ContentSource = "Header"
                                  VerticalAlignment = "Center"
                                  RecognizesAccessKey = "True" />
              </DockPanel>
            </Border>
            <Border x:Name = "InnerBorder"
                    Margin = "0" >
              <ContentPresenter Focusable = "false"
                                Visibility = "Collapsed"
                                HorizontalAlignment = "{TemplateBinding HorizontalContentAlignment}"
                                Margin = "{TemplateBinding Padding}"
                                x:Name = "ExpandSite"
                                VerticalAlignment = "{TemplateBinding VerticalContentAlignment}"
                                DockPanel.Dock = "Bottom" />
            </Border>
          </DockPanel>
        </Border>
        <ControlTemplate.Triggers>
          <Trigger Property = "IsExpanded"
                   Value = "true">
            <Setter Property = "Margin"
                    TargetName = "InnerBorder"
                    Value = "5" />           
            <Setter Property = "Visibility"
                    TargetName = "ExpandSite"
                    Value = "Visible" />
          </Trigger>
          <Trigger Property = "IsEnabled"
                   Value = "false">
            <Setter Property = "Foreground"
                    Value = "{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}" />
          </Trigger>         
        </ControlTemplate.Triggers>
      </ControlTemplate>
    </Setter.Value>
  </Setter>
</Style>

Как видите, есть два ContentPresenter. Я бы хотел, чтобы первый использовал в качестве шрифта Tahoma Bold вместо стандартного Tahoma. Как я могу это сделать?