Sorrow breeds a monster come morrow

A saying among the populace of the Solstrum Principality. It refers to how those suffering greatly can succumb to Spontaneous Monsterficiation -prob change name-, scurs or molting. In conversation its used to remind people not to associate with those showing great sadness out of fear they might turn into a monster. 
Example. Farmer Johan lost his wife and kids in an attack and is depressed.  "Johnny you shouldn't come near Johan anymore. Sorrow breeds a monster come morrow." Which means = Johnny you should avoid farmer Johan. He might turn into a monster and kill you because he is depressed.