It is my understanding that when you reach level 48, your teacher gives you a quest that once you complete it, gives a school-specific pet, and the seven-pip spell specific to your primary school. I think that you should also be able to do a similar quest for your secondary school, if you learn all of the spells from the teacher there and reach level 48, that allows you to obtain the pet specific to that school. Let me know what ya think. Thanks for reading. :-)