Secrets
You will need to find secret rooms or do specific actions to get those.
Denial / At the very beginning of the game, go right until you can move freely, then come back to the left and find a statue. Let your character fall and get up from herself.
Anger / In the black & white area of chapter 2, slam the 3 fragile statues. (don’t slam for nothing or you will get ejected!)
Bargaining / After some big red bird jumps, you will face a statue, press B to (try to) sing in front.
Depression / During the water chapter, in the big area where you need to have 6 stars, head to the bottom and search to the left, you will find a statue and get the achievement.
Acceptance / During the final sequence, just after getting to the surface of the black water, sing in front of the tomb.