title: how to get objects from relation of relation in laravel
body: <p>I have 3 model: Course,group,student</p>
  
  <p>I want to give games from Course with 2 relations.</p>
  
  <p>for ex: I want students of Course 1 (id=1)</p>
  
  <p>The Course has Many group(5,6,8) and each group have One(36,38) or Many(35,37) students</p>
  
  <p>How to get all students of Course with relations and eloquent</p>