title: How to specify Parent-Child relationship within one Model?
body: <p>For example I have following code:</p>
  
  <pre><code>class FamilyMember(models.Model):
      user = models.OneToOneField(User)
  </code></pre>
  
  <p>And I have following situations:</p>
  
  <pre><code>a1 = FamilyMember.objects.get(id=1)
  a1.first_name = 'John'
  a1.last_name = 'Smith'
  (a1 is a parent of a2)
  
  a2 = FamilyMember.objects.get(id=2)
  a2.first_name = 'Mark'
  a2.last_name = 'Smith'
  (a2 is a child of a1 and parent of a3 in the same time)
  
  a3 = FamilyMember.objects.get(id=3)
  a3.first_name = 'Jason'
  a3.last_name = 'Smith'
  (a3 is a child of a2)
  </code></pre>
  
  <p>How can i accomplish that kind of relationships within one model ?</p>