Window

If you tap on the window in either of the upstairs rooms, you'll be able to look outside.

Milk
Milk will be delivered periodically with a bit of wisdom. Tapping the milk will earn you some hot and cold water. Tapping the milk holder when it is empty will tell you when the next delivery is.

Clickable Appearances
Periodically, various things will appear in the window view and tapping them will give you some hot and cold water. They only appear for a limited time so be sure to check back often!