Among the Sleep

[Ashtoreth]

Agreed.
All the hints! They are there!
And if you play the game a second time you will suddenly realize more stuff:

Spoiler below!

In the beginning when you are carried by the mother and walk past a closet to get up the stairs, what's in the closet?
It's a fucking coat!
The coat monster! Aaaah!
(I'm not mentioning this because if you look in the closet then yes, there is a coat and there are multiple places. But they focused on it! The closet is open just enough so that you can see it! You're supposed to see it!)

Also, one cool thing. The monster doesn't kill you. The monster doesn't break your neck. It picks you up... Just like mother does.

When the coat monster is around, the mothers voice is playing.

Well observed!

I started a new game and I detected another hint right at the beginning. Now that I know what the game is about, it seems so noticeable, haha.

Spoiler below!

Red wine stains on the jumper that the mother is wearing!