 
Jack explanation: the rabbit has already eaten his cake (hence the crumbs), the hamster is sad because he thinks the rabbit is going to eat his next.
 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                
                 
                 
                 
                 
                 
                 
                 
                 
                 
             
Jack explanation: the rabbit has already eaten his cake (hence the crumbs), the hamster is sad because he thinks the rabbit is going to eat his next.