title: Laravel findOrFail does not exist
body: <p>When I use findOrFail in my code it doesn't work</p>
  
  <p>I've tried the find method and it works as I expected</p>
  
  <pre><code>public function show(Question $question, Reply $reply) {
      return $question-&gt;replies-&gt;findOrFail($reply-&gt;id);
  }
  
  BadMethodCallException: Method Illuminate\Database\Eloquent\Collection::firstOrFail does not exist. in file
  </code></pre>