Looks like a great dark thriller with supernatural elements. Apart from the supernatural elements, a female protagonist with a kid and focus on the bond between siblings are unusual features in a thriller. I’m also getting hints that the supernatural elements are time-related in an odd way. It’s a bit dark for my taste and seems a little over the top deliberately tragic that the character’s brother gets attacked the one time she left him alone (despite him clearly being old enough to not need constant supervision).