Yeah, two things that I'll need to grab at free resources for will be sound and music. Good luck with you as well!
I did settle on one idea so I've jotting down the idea in more detail. It is simple to start with but I loved fairytales as a kid like the Snow Queen, Godfather Death, and Vasilisa the Beautiful more than Snow White and Rose Red, Little Mermaid (with and without the "be good kids for she will suffer disproportionately more" shoehorned moral), or The Twelve Brothers... to say nothing of The Juniper Tree (one of the most wicked stepmothers I remember reading ever).
It didn't even take five seconds for it to explode into something more complex just in the intro alone because the number of siblings would affect the story in different ways thanks to the frequent motif of "youngest child wins by being cunning af".