Violet was a doe who came from Sandleford with Hazel, Fiver, Bigwig, and others, only appearing . Tragically, she was the only hlessi in the group that never reached Watership Down, as she was killed by a hawk. Hrairoo(Fiver) was the only rabbit to witness her death. We do not actually see her death, as the screen blacks out when the hawk strikes and takes her away. She had sacrificed herself to save her friends.
She was the only female rabbit to accompagny the group, so when she died, Hazel's new anxiesty became how to get some does with him and he started to risk much to find new females.