Nessarose

Elphaba's invalid sister

Nessarose Thropp is Elphaba's sister. Gregory Maguire named her after Virginia Woolf's sister Vanessa, known as "Nessa." According to the novelist, she was born both crippled and armless. On stage she has arms but is in a wheelchair.

Source: http://www.musicalschwartz.com/wicked-characters.htm