Check if two family members are cousins.
        
        If two individuals share any grandparents they are cousins.
        
        Arguments: 
            individual_1_id (str): The id of an individual
            individual_2_id (str): The id of an individual
        
        Returns: 
            bool : True if the individuals are cousins
                   False if they are not cousins

def check_cousins(self, individual_1_id, individual_2_id):
        """
        Check if two family members are cousins.
        
        If two individuals share any grandparents they are cousins.
        
        Arguments: 
            individual_1_id (str): The id of an individual
            individual_2_id (str): The id of an individual
        
        Returns: 
            bool : True if the individuals are cousins
                   False if they are not cousins
        
        """
        self.logger.debug("Checking if {0} and {1} are cousins".format(
            individual_1_id, individual_2_id
        ))
        
        #TODO check if any of the parents are siblings
        pass