title: EF Core Second level ThenInclude missworks
body: <p>Assume having these models first:</p>
  
  <p><code>Method</code> that has one <code>OriginalCode</code>
  <code>OriginalCode</code> that has many <code>Mutant</code>s
  <code>Mutant</code> that has many <code>ParseSubTree</code>s</p>
  
  <p>Now when querying on <code>Method</code> I want the other being loaded. So I have the following:</p>
  
  <pre><code>Method targetMethod = dBContext.Methods
              .Include(me =&gt; me.OriginalCode)
                  .ThenInclude(oc =&gt; oc.Mutants)
              .FirstOrDefault(me =&gt; me.Id == id);
  </code></pre>
  
  <p>and the next step is to include additionally the <code>ParseSubTree</code>. But the thing is that I can't access it. See the following Image:</p>
  
  <p><a href="https://i.stack.imgur.com/e9CZc.png" rel="noreferrer"><img src="https://i.stack.imgur.com/e9CZc.png" alt="mu is a list except object reference"></a></p>
  
  <p>the problem is "mu is a list instead of being an object reference"!</p>
  
  <p>Where is my mistake!</p>
  
  <p>TG.</p>