These races are free for children ages 2 - 9 and kids are divided into the following age groups: 2 - 3, 4 - 5; and 6 - 7, 8 - 9. (carolinaparent.com)
In general, cats can be divided into the following age groups: kittens (0 to 12 months old), adult cats (1 to 6 years old) and senior cats (7 years and older). (petpeoplesplace.com)
In general, dogs are divided into the following age groups: puppies (0 to 12 months), adult dogs (1 to 7 years) and senior canines (7 years and older). (petpeoplesplace.com)