Near the end of Charmed Life, Chrestomanci tells Cat that he knows how he's feeling after discovering Gwendolen's betrayal, who Cat looked up to. At first it seems like he is sympathizing with him over the betrayal. However, in The Lives of Christopher Chant, it's revealed that Christopher was duped and used by his own uncle, who he looked up to and adored, and had to discover this in the worst way possible. Chrestomanci really does know what Cat's going through.
The similarities between Cat and Chrestomanci. Both are Chants, both discovered they were nine-lived enchanters at a young age, both of them were badly used by a relative they looked up to and adored (Gwendolen for Cat, Uncle Ralph for Christopher). They both lost their lives at an alarming rate. They also both befriended a girl from another world who chose to stay in 12-A, and tried to run away from Chrestomanci Castle at one point.
Fridge Horror
The fates of the Living Asheths that Mother Proudfoot wasn't able to rescue.
