The importance of the nurse is that she is Juliets best friend and airgo her shoulder to cry on and advice giver who helps her out of hot water so she helps her with Romeo. Think of her as Juliets...
But soft! What light through yonder window breaks? It is the East, and Juliet is the sun! Arise, fair sun, and kill the envious moon Who is already sick and pale with grief That (1) thou her maid (2)...