Who is Elena Vilkas from Between Shades of Gray and what is their importance?

Elena Vilkas is Lina's mother. She speaks Russian, and thus, becomes an interpreter between the guards and the prisoners. She is described as a determined woman with impeccable manners, and when she is offered the job of a spy for the Russians in exchange for extra rations, she refuses. Elena believed that a clear conscience was worth more than the promise of food. Her generosity and kindness served to be a great influence on her children.