The room which contains the face as well as the strange hole in which an item should be placed outside. Inside the room, if you apply the face from the tombstone of Mike, the place crumbles for a moment. If you look at the door while the earthquake is happening, you can see the rooms appear to be falling past the door at high speeds. When it stops, you are able to enter the door located on the right. The player is then sent to Mike’s room, with an upcoming message. You can also apply the face on the Flower Shack, this opens the door to Care’s Bedroom.
The name "Child Library" may be a metaphor for foster care, where children could be thought of as being "borrowed". Others have suggested it may have a human trafficking implication.
If you calculate the total number of possible rooms, you end up with 288,000 unique “faces”/bedrooms. This number may or may not be significant. The original calculation used for calculating this number came up with 144,000, which interestingly does have biblical ties to rebirth. For now, this theory may be busted, but if you’re curious, just google “144,000 rebirth”.