Chocola the Chao

From the Sonic News Network, the Sonic Wiki

Chocola is a sibling of Cheese the Chao, and both belong to Cream the Rabbit. Chocola is similar to Cheese, differing only in brown coloration and blue bowtie. In Sonic Heroes, Team Rose went on a search to find him and Froggy, who had both been kidnapped by Metal Sonic to absorb data of their contact with Chaos (which might be weird since Cheese never came in contact with Chaos at all). Chocola hadn't appeared since.

Chocola is often regarded as a filler character for Sonic Heroes, created only to act as an appropriate motive for Cream the Rabbit without requiring a separation between Cream and Cheese, as Cream relies heavily on Cheese to battle and survive.