Elizabeth is a mouse living in the walls of Dook's home. She doesn't socialize much with the animals on either side of The Window, and when she does, she can be very distant and soft-spoken...until she starts to sing. After hearing Dook's untrained voice, she decided to give him singing lessons so he wouldn't embarrass himself around her again.
Max is a mutt that lives in the same complex as Dook. On occasion, his owner will drop Max off at Dook's owner's place. Max's favorite pastimes are barking while hiding behind something (or someone), chewing on stuffed animal ears, giving Dook (and now Chessie) lots of kisses, and chasing down that elusive red dot that shows up from time to time.
Where Dook has Chessie, Elizabeth has Max.