Peter Warren Hatcher
The main character, Peter is a nine-year-old 4th grader living in New York City with his family. He is a hardworking, quiet, easygoing kid normally, but when his brother Fudge starts creating trouble, his attitude changes.
Farley Drexel "Fudge" Hatcher
Peter's two-and-a-half year old brother is a bit of a terror. He causes all sorts of trouble, misbehaves, and doesn't listen to his parents, driving Peter crazy. He does look up to Peter as his big brother though, and constantly wants to follow his example.
Mrs. Hatcher
Peter and Fudge's mother, she is a devoted mother who keeps the house running as smoothly as possible and worries a lot about her children. However, she sometimes frustrates Peter when she takes Fudge's side over his.
Mr. Hatcher
Peter and Fudge's father, he is a more easygoing parent than Mrs. Hatcher, but does discipline Fudge more harshly when necessary. He works at an advertising agency.
Jimmy Fargo
Peter's closest friend, he is also in his fourth grade class and lives in an apartment on his block. The two often hang out in Central Park together.
Sheila Tubman
Another fourth grader from Peter's class, she lives in his same apartment building. Peter thinks Sheila is a know-it-all and does not like her very much. When Peter, Sheila, and Jimmy are assigned to do a school project together, Sheila is bossy and tries to take control of the entire assignment.
Dribble
Dribble is Peter's turtle and his very first pet. Peter wins Dribble at the beginning of the book, during carnival games at Jimmy Fargo's birthday party.
Grandma
Peter and Fudge's grandmother, she often comes over to help their mother with things around the house. She assists in supervising Fudge's chaotic third birthday party.
Mr. Yarby
He is the president of Juicy-O, which is the juice company that Mr. Hatcher's firm is advertising for. He and his wife come to stay with the Hatchers in Chapter 2.
Mrs. Yarby
She is Mr. Yarby's wife and is very afraid of reptiles.
Henry
He is the elevator operator in the Hatchers' building.
Jennie
She is a little girl who sometimes plays with Fudge. She comes to Fudge's third birthday party, and causes trouble by biting Peter's grandma and peeing on the floor on purpose.
Ralph
He is a little boy who Fudge sometimes plays with, and who comes to his third birthday party. Ralph is overweight and is constantly eating.
Sam
He is another little boy who sometimes plays with Fudge. At Fudge's third birthday party, he is going through a phase in which he is afraid of everything, and constantly cries.
Dr. Brown
The family's dentist, he is a friend of Mr. Hatcher.
Mr. Berman
He is the family's favorite shoe salesman at Bloomingdale's.
Linda
She is Mrs. Hatcher's sister and has a new baby during the book. Mrs. Hatcher flies to visit her, leaving Mr. Hatcher and the boys alone.
Janet
She is Mr. Hatcher's secretary and takes the boys on a tour of the office when they come into work with him.
Mr. Vincent
He is the president of Toddle-Bike who wants Fudge for his commercial.
Dr. Cone
He is the doctor who takes care of Fudge at the hospital after he swallows Dribble.
Turtle
Turtle is Peter's new dog that he receives at the end of the book, after Fudge swallowed and killed his pet turtle.
