I apologize for all the edits but this keeps growing so adding all necessary info as it appears in comments save all the digging through.
Edit: So adding this post https://voat.co/v/pizzagate/2291627 by our collegue @Piscina that shows how the Vanderbilts worship Lucifer, as this post contains pictures and photos from their estate which will help my post make more sense to the new comers and refresh some others.
Edit: So this was covered in a post 8 months ago now in this by Sryazie:
Seems to have gained some views but I guess some of us missed it, as I did.
Just came across this on Twttr.. So thanks to those that made the connection, I Am just sharing it here as it could be a vital clue!
Thank you also to those in this link!
Here's a video of the real pool.... Similair pool as the painting..
Thank You @3141592653 for adding the video below! Awesome, but sickening..
EDIT: Here's a quick enhancement and edit of the real pool photo from what is said to be the place of the painting with the little boy hanging up, you can almost make out where the X in the paint on the tiles was. The middle of the X is above the light and then it goes off on the same angle and direction both sides.. And I do not feel this is because of a trick of light.. The X is clearly darker (was painted?) than the other tiles.
And to those that say the tiles are coloured in the paintings that could just be the artists addition and also as to not have it exactly match the photo the painting has been done from.
Thanks to others for the above photo!
EDIT: Ok so what else it quite strange about this "pool" is it's complete lack of steps going to the bottom of the ladder, I mean even if it was full of water, would you still not take the steps most of the way down? I know it is probably accessible from the end the photo is taken but would it still not make sense to take them down to an accessible point whilst the "pool" is empty?
Said ladder: https://imgur.com/a/WQQVao5
And also those talking about no drain, is that what the black pipe in this picture is?
EDIT: Here's the "artist" that did the paintings of the tortured kids. Sick stuff here so please be advised. and there is also the dentist chair that has become quite relevant throughout all of this:
EDIT: So long shot.. But could the guy on the far left in this photo https://imgur.com/a/XzQgQdy be a younger version of this guy https://imgur.com/a/olYCOOB ??? Vanderbilts grandson..
Could also be the same area: https://imgur.com/a/aHooW4W
EDIT: This is an image of the waterfall located just outside of the Estate and has a small drain right next to a bigger drain which could be easily used as a tunnel/access: https://imgur.com/a/mwwxRzS
EDIT: Another painting by the same artist that shows some vicious dogs being held by some creepy men, the man on the left appears to be holding a club of some sort: https://imgur.com/a/OGUZNSv
Which almost resembles the same clubs hanging in the Biltmore Estate gym that also has the same white tiles we see repeated in her paintings: https://imgur.com/a/LzuqAup
According to G--gle this is in their winter garden https://imgur.com/a/RuyfkJD it seems as if without the metal grate it would be a secret passage and why the metal grate? Maybe for the tours it has been placed there but either way it makes it all the more creepy.
Edit: This is a thread from Reddit that talks about the tunnels below the Estate- https://www.reddit.com/r/greatawakening/comments/98c2ll/about_the_biltmore_pool_found_this_while_looking/?sort=top
Thanks to @exposethecriminals for adding and to those at Reddit.
Edit: Almost matching wallpaper in the Louis room in the estate https://imgur.com/a/hTLiz8t as this painting by the same artist https://imgur.com/a/C1cQTtR
Edit: So I think it's safe to say we can match MANY of the rooms in the estate to the paintings done by the artist!
Here are photos from a Pintrest page https://www.pinterest.com.au/pin/151222499959337200 which are almost identical to the paintings by the artist above.