Friar Laurence discovered Juliet supposedly dead on Thursday morning.
The Nurse did.
Thursday, then Wednesday.
Thursday
It was moved forward a day (from Thursday morning to Wednesday morning). This meant that the Friar had to rely on a letter to tell Romeo of Juliet's fake death.
Juliet's Nurse
Juliet's parents plan for her to marry Paris on Thursday.
The Nurse finds Juliet apparently dead after she has taken the Friar's knockout potion.
In Romeo & juliet, on thrusday, Paris plans on being marred to Juliet.
To get married to Paris, on Thursday
Juliet was originally supposed to marry Paris on a Thursday, but she submitted to her fathers will, and married him a day earlier....making it a Wednesday. She took the potion on the Tuesday night before the wedding, and was found "dead" by the Nurse. Juliet did this so she would not have to marry Paris.
Juliet is found by her nurse the next morning after she takes the potion that makes her appear dead.
Juliet was given the sleeping potion on Tuesday, and was supposed to drink it on Wednesday night, but Lord Capulet changed the wedding date to Wednesday so Juliet drank it Tuesday night. Juliet woke up late Thursday night or early Friday morning and killed herself. So she was sleeping for about two days, forty-two hours to be exact.