 Fiver : A runt rabbit whose name literally means " Little Thousand " ( rabbits have a single word , " hrair " , for all numbers greater than four ; Fiver 's name in Lapine , Hrairoo , indicates that he is the smallest of a litter of five or more rabbits ) and Hazel 's younger brother . As a seer , he has visions and very strong instincts . Fiver is one of the most intelligent rabbits in the group . He is quiet and intuitive , and though he does not directly act as a leader , the others listen to and follow his advice . Vilthuril becomes his mate . 
