Alvin wanted to name her "Chomper," Theodore wanted to name her "Cookie," and Simon wanted her to have a more sophisticated name, so they decide to call her Cookie Chomper III. Dave agrees to let them keep her and even buys a collar and tag for her to wear. Simon also helps Dave overcome his allergy to cats.
However, soon after Cookie Chomper III is hit by a car and killed. Dave helps the boys deal with their grief and embrace the memories of their brief, but happy, time with Cookie Chomper III.
The boys sing "Beautiful Memories" in remembrance of the kitten.
- Like Cookie Chomper III, Tiger Lilly, Ross Bagdasarian, Jr. and Janice Karman's dog, was also run over by a car and killed.
- They later adopt Lilly, a small brown dog.