public void WriteToJson()
 {
     var family = new Family();
     var me = family.Add("me");
     family.Add("mom").Is.TheParentOf(me);
     family.Add("dad").Is.TheParentOf(me);
     DebugWrite(family);
 }
 public FamilyExtensionsTests()
 {
     _us = new Family();  _dad = _us.Add();  _mom = _us.Add();  _brother = _us.Add();  _sister = _us.Add();  _cat = _us.Add();
      _expectedChildren = new List<Person> { _brother, _sister, _cat };
 }