Abigail narrowed her sapphire eyes, trying to see if the room ever ended. Shadows danced in the corners of the chamber, rearing and rising to the high ceiling, twirling and churning like monsters in the gloom.This is really picky, but saying that twirling and churning makes it look like a monster seems a little odd to me. Maybe twirling and churning like a ghostly gown, or phantom fog, or whatever, but it just sounds a little weird.
The Shadows had told Abigail to keep the room a secret, but Abi wasn’t supposed to lie… she shrugged her petite shoulders. Another small thing, this seems too simply-put and blunt. I think it could be more along the lines of implied.
Things had gotten worse for everyone when he learned to walk, but he still couldn’t talk nor did he seem to understand what people said to him other than the basics.
“Uncle Joseph said to call him Daine because he doesn’t like his name and being called Uncle makes him feel like an old man.” Unlike Jakob, Alex learned to talk at an early age and his speech was almost perfect though he was only four, almost five. I like how you're developing your characters, my only piece of advice is to tweak this last sentence, because it's a run-on.
having abandoned the boxes he was bringing in on the porch.