This character is first seen at the Animal Rescue Center in the beginning of the movie. It is presumed that Bolt was given the toy to play with while he was taken care of at the center, and he quickly grew attached to it.
Mr. Carrot does not develop much in the movie and shows no particular characteristics, partly because his role in the movie was not as central as many of the other characters, partly because he is a squeaky toy.
Mr. Carrot is Bolt’s favorite toy and has been from early puppyhood, making him one of the hero’s more intimate childhood friends. Mr. Carrot also holds a distinguished emotional value for Bolt reminding him of times he has shared with Penny. Bolt is still seen playing with Mr. Carrot after settling down in Penny's house after his great adventure.
Mr. Carrot was met generally well be critics, cited as a both funny and deep character. Some critics. however criticized the carrot's notable lack of dialogue in the film, but most movie critics agreed that Mr. Carrot is still by far more complex and evolved than Rhino, the hamster.