Based on @lunas-asks-and-reblogs ‘s idea, here I present you
The grim weavers of shadow (based on the charms Grimmchild, Weaver Song and Sharp Shadow)
These four sisters form a strange cultist-like family born of no parents...except if you consider this tale: long ago nightmares and shadows, alike yet apart, found one another in a weaver’s husk fallen into the void. The spider was a mother, who held in her paunch four eggs. After days and months, the first one broke, and the new born was able to drag the three other out of the black lake.
And so was born the first sister. The second hatched, then the third, then the fourth.
In death they last eternal, slave to an unending circle, where the eldest succombs and is rebirthed soon after, becoming the youngest one.
First stage: the sister is unable to wander on her own, and the void within her is dimmed.
Second stage: the sister has grown, her physical envelope is tougher. Thick feathers have appeared on her torso, and from them already leak drops of nothingness. The void within her has started to awake.
Third stage: in her eyes already burn the flame of nightmare, and her body is starting to melt into void. Bandages are needed at this point, in order to hold her form together and shape the shadows into something that will grow looking as normal as possible.
Fourth stage: the final one. The sister has grown big, and already in her belly grows an egg, of shadows and tourment, that contains her future form. Her body melts into black substance, and is hardly stable.
But only when emptiness itself will slay her will she be allowed to rest...for a while that is.