In Lily's letter to Sirius, she mentions how Harry nearly killed the cat with the toy broom that Sirius got him. Well, what if that's the reason that Crookshanks has a squashed head and a flat face? <<< This makes perfect sense!
Theory: Why Peter Pettigrew's name didn't appear on the Marauder's Map While I agree with this theory. Didn't Harry see Peter on the map before Harry knew he was an animagi? >>> he could have been in human form for a second.