Upper moons and baby Tanjiro

Who???

It's been three days since Muzan locked him down there.
A growl breaks the silence in the dark room and a quiet sob escapes the boys blue tinted lips as he shivers, curling into a ball trying to find warmth in himself. He's hungry, thirsty and tired.
It's been three days since Tanjiro has eaten, three days since he has had anything to drink. Three days since he's has a good nights rest. Three days in the dark, cold basement. Three days since he snuck out.
It's been three days and that door finally opens again.

Soft footsteps make their descend down the stairs and towards the boy. Poor Tanjiro doesn't even have the strength to lift his head to see who's there. All he can do is snuggle into the warmth of the person holding him.

?? POV

'This boy, he's so small. Shouldn't he be bigger?' I can't help but wonder what the hell is going on. They told me to gather him from the basement and tend to him. But why was he down there in the first place. And why is he still so damn tiny?
Finally reaching his room, I place him on the bed. He's passed out from now, but very cold. He hold onto my shirt quite tightly when lean in to cover him with blankets. But he quickly latches onto a stuffed bear in replacement.
   Now that I look at him, he's actually a very cute child. I'm not sure what I was thinking before hand.
  "He's going to need food when he wakes, I'll make him something. You get him some water and monitor him." My brother tells me from the door
"Get him some soup. I've heard it's best for humans who haven't eaten anything in a while, and some bread."
'His face is so thin' I think as a slid a finger down his face and neck. 'Oh well, I should go get him that water. Maybe start a bath for him too, he's filthy."
  After bringing in his water, I move to the bathroom. It's there I pass Rui, lower 5, he doesn't say anything, but gives me a nasty glare. I shouldn't feel intimidated, I'm stronger then him. But knowing who's got his back makes it harder.
Quickly finishing up the bath, I make my way back to his room, where he's slowly starting to wake.
" take it easy Tanjiro, it's all right." I try to calm him down, but he keeps tossing and turning. After a couple minutes he finally sits up with a gasp, and starts violently coughing and wheezing.
" Here, drink some water" I hold the glass out to him, but he doesn't take it.
"C'mon, he's gonna be so mad, you need to drink something!" I bring the glass to his lips, tilting his head back to help him drink. It works, but he's just staring at me with wide eyes.
"W-why are you here?" He rasps out
" I was told to be, I'm not going to hurt you"
He just keeps staring. 'This brat'
"My brother is going to bring you some soup, do you think you can keep it down? You must be hungry" I tell him, hoping for some kind of reaction. His staring is starting to get creepy. Thankfully, he nods, and his stomach growls.
  A few minutes pass and I here my brother coming towards the door.
"I've got the soup for him Daki, is he awake yet?".