XAML: How do I make part of a GroupBox Header bold?
<p>I need to make the first part of a GroupBox Header bold, and the other part non-bold. Here is the goal I'm trying to achieve:</p>

<p><strong>Students</strong> (Max: 32)</p>

<pre><code>        &lt;GroupBox Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="4" Margin="40, 80, 40, 80"&gt;
        &lt;GroupBox.Header&gt;
            &lt;Span FontWeight="Bold"&gt;Students&lt;/Span&gt;
            (Max: 32)
        &lt;/GroupBox.Header&gt;
        &lt;StackPanel&gt;
        ...
</code></pre>

<p>This gives me the error: The property "Header" is set more than once.</p>

<p>I know that it works for TextBlocks, but I can't make it happen for GroupBox Headers:</p>

<pre><code>        &lt;TextBlock&gt;
            &lt;Span FontWeight="Bold"&gt;Students&lt;/Span&gt;
            &lt;Span&gt;(Max: 32)&lt;/Span&gt;
        &lt;/TextBlock&gt;
</code></pre>

<p>Thanks.</p>