A person should be loyal.
Act 1 Scene 3
The nurse is speaking to Lady Capulet about how she has nursed Juliet so long by saying in the play, "I remember it well. 'Tis since the earthquake' now eleven years; and she was weaned..." (1006 lines 26-30.) The Nurse has been by her side for many years and hasn't left. She is showing loyalty because she was always there to help Lady Capulet care for her daughter.
Act 2 Scene 4
The Nurse is speaking to Romeo about if Romeo can marry Juliet, and in the play it states, "I will tell her, sir, that you do protest, which, as i take it, is a gentleman like offer." The nurse is being loyal to Romeo and Juliet's decision by keeping their marriage a secret and for helping Romeo prepare by getting Juliet.
Act 3 Scene 3
Nurse is speaking to Romeo about Juliet and how she thinks something is wrong. As moments before the Nurse said the words, "O, she says nothing, sir but weeps and weeps..." (1058 line 114.) The Nurse shows she is being loyal to Juliet by helping her when she is sad, and trying to figure out whats wrong with her.
Act 4 Scene 4
The Nurse is speaking to Capulet so he goes to bed and doesn't get sick for not getting enough sleep. It shows in the text the nurse says, "Go you cot-quen, go, get you to bed! Faith, you'll be sick tomorrow for this nights watch." (1080 lines 9-11.) The Nurse is helping Capulet so he doesn't get sick and is telling him to go to bed. This shows her being loyal because she is caring about his health.