"'You need to rename that stupid cat.'" -Number Nine, United as OneStanley is a Chimæra who was on the second ship from Lorien. He was only mentioned in The Revenge of Seven.
He lived in a menagerie owned by Ella's father, Raylan. Stanley is one of the Chimærae that Adam rescued from the Mogadorian facility on Plum Island in the events of The Forgotten Ones. In The Revenge of Seven, Sam befriends him in the form of a fat orange cat, and chooses to name him Stanley, after Number Nine's alter ego, as he believes the fat cat has a resemblance to Nine.
Stanley was in an abandoned warehouse with the other Chimæra, John, Sarah, Sam, Malcolm and Adam. He was left back at Ashwood Estates to protect Malcolm, but was moved to a secret bunker along with Malcolm and the rest of the Chimærae in Last Defense.
In United As One, Stanley is seen comforting Sam before the final battle on the West Virginia base. When Sam calls Stanley by name, Nine scowls, telling him he needs to rename the cat.