Crack in a china teapot that goes thru to the outside?

Nothing seemed to leak thru tho. I used the method with allowing milk to sit for nearly a week that you recommended for my smaller teapot. It worked beautifully. Now I need to know about a larger teapot belonging to a friend. Hers is the one that is cracked on the outside too. I filled it above the crack with milk, allowing it to sit for a week, and while it helped, it was still visible on the inside, and no change on the outside. If I fill a large vessel with milk, submerge the teapot and filling it with milk again, allowing it all to get really really smelly, like over a week, would this heal the outter crack?