The Nursery is the last room in the first area appearing in Luigi's Mansion.
The area is a baby's room and the home of the area's boss Chauncey. Despite Chauncey being a boy, many pink things are in the room to make it look like a girl's bedroom. It also houses his crib and Rocking horse.
When Luigi enters, Chauncey is seen sleeping in his crib. In order for Luigi to wake him, Luigi must use his Poltergust 3000 to rock the horse on the bottom-left area. Chauncy then says he wants to play and chases Luigi by throwing balls at him. Luigi hits him with this ball and Chauncey shrinks him after throwing a fit and places him in his crib. After a fight, Chauncey is defeated and the second area is accessible.