Though it's probably obvious to everyone that the adults don't appear often it's pure truth that every time they appear they somehow change the lives of one animorph or another. For example when Marco's dad started working on some big project at work which turned out to be a yeerk trap, or when Jake lost his parents and Tobias found his." it was weird. Like we had traded places, Tobias the orphan had a mother now and Jake the boy with the normal all american nuclear family was alone. Since both Tobias and e's favorite looking at the whole thing Ax didn't have parents they relied on each other. We were the strangest couple in the universe the Bird-Boy and the alien. Marco's mother's death and her turning out to be Visser One also played a major role and was a huge blow to all the animorphs. It seems like Cassie is the ownly one of the members as the least affected . She still remained the same. Personally i think she was K. A .A pplegate Considerthe fact that in the end All the other animorphs died. All i'm saying is , no matter how frustrating inappropriate and provoking can be , they're still family.