title: PHP site changes with Get parameters
body: <p>so I have this really weird bug and I have no idea why it occurs:
  I have an "index.php" with header and footer and in the middle it includes a "Content.php", that outputs the content, depending on which Get-parameter the index.php has:</p>
  
  <pre><code>if($_GET["site"]){
      switch($_GET["site"]){
          case 1:
              break;
          case 2:
                  if($_GET['horses']){
                      include_once("horses.php?horse=".$_GET['horses']);
                  } else{
                      include_once("horses.php");
                  }
              break;
          case 3: include_once("contact.php");
              break;
          case 4:
                  if($_GET['members']){
                      include_once("team.php?member=".$_GET['members']);
                  } else{
                      include_once("team.php");
                  }
              break;
          case 8: include_once("pressestimmen.php");
              break;
          default: include_once("home.php");
      }
  } else{
      include_once("home.php");
  }
  </code></pre>
  
  <p>In some cases (horses and Team members) a second Get-Parameter is passed that is processed inside the corresponding Content-file.<br>
  This works perfectly well for the horses and behaves as expected but for some reason, even though I copied the code (except some details) in the "team.php" NO content at all is shown, when I pass a Get-parameter. This in itself wouldn't be too suprising, as I might have a bug in the php somewhere but even when I change team.php to:</p>
  
  <pre><code>&lt;div class="margin-bottom-30"&gt;
  &lt;/div&gt;
  &lt;div class="tabs"&gt;
      &lt;ul class="nav nav-tabs"&gt;
  
      &lt;/ul&gt;
   &lt;/div&gt;
   &lt;div class='tab-content'&gt;
  
  &lt;/div&gt;
  </code></pre>
  
  <p><p>
  When I call "index.php?site=4" it works without problems and shows the empty containers. But when I call "index.php?site=4&amp;members=1" the Content is completetly empty and I don't understand how this is even possible considering html shouldn't even notice the get parameter. <br>
  I've tried to fix this for hours and I just can't figure out how the Get-parameter could possibly affect the html code inside team.php</p>