Animal Companion is a half-baked ability, in that the second pet is picked from the first slot in the pet journal. That means that even though you can call out one of 5 pets, without visiting the stable master (or using a repository), you cannot choose the second pet.
As I would like my two pets to match, I would like more control over the second pet offered with Animal Companion, so for example if I pull out a wasp, the second pet is also a wasp. If I pull out a cat, I would like the second pet to be a cat also.