title: Border with more then one child
body: <p>I have a Border.</p>
  <p>I have a TextBlock displayed on it:</p>
  <pre><code>TextBlock tb = new TextBlock();
  myBorder.Child = tb;
  </code></pre>
  <p>And it works fine.</p>
  <p>The thing is: I also want to have CheckBox displayed on it.</p>
  <p>The problem is that border is a single child element.</p>
  <p>Is there any workaround here?</p>
  <p>Thank you!</p>