He's trying to kill us--could ruin him--worry about that later--grab your sister and go.
"...Weird. You actually have to talk and gesture? I think my magic's better if it's possible to take away yours by binding and gagging you."
"No, but I was fleeing a murder attempt when I came here,and my brain hasn't gotten completely out of paranoid mode yet."
"Yeah, probably. ...So, um, I'm...not really sure what to do with myself at this point. I'm not even sure whether my sister's still facing down death by irate teacher or not."
"I haven't measured it recently, but pretty large. Comparatively speaking. Hundreds of miles."
"Almost certainly not. Well, is there anything wizards mostly can't do that I might be able to?"
"Nope and don't even know what that means. Damn. There's probably something, but--oh. Hm. I could de-age people, I think I saw enough old people that that's not redundant, at least."
"Oh! Yeah, wizards don't do that. You probably want a big commercial caster office with a huge network and maybe you can work something out where they call up their big customers and have you de-age them and then you can get a translation spell and a scry for your sister and a call or summon depending."