You get this automatically after collecting the third emblem drawing in the dollhouse.
The first emblem is found in the basement near where you fell, behind the door with the wooden bar over it (it also smells bad as per James). You need the axe from Barron's closet to open the door.
The second emblem is found behind the plant. You need to mix the alcohol, salt and vinegar together to make the mixture to kill the plant.
The third emblem is found in the dollhouse. You need to type the code to gain access, then grab the key at the very right of the screen after you talk to the doll. Then open the closet on the third floor to access the emblem.