This always seems to happen: Somebody comes out with a hit song, hit book series, hit movie, hit TV show...and then the "hit" hits the fan! People come out of the woodwork claiming the hit "stole" from their works. They file a lawsuit, seeking millions in damages, cancellation of the hit, and if not cancellation, give them screen credit.
The latest "you copied" lawsuit is from a Peruvian author named Isabella Tanikumi, who claims Disney "stole" her life story as the basis for the hit animated feature "Frozen"--never mind that it's really a retelling of Hans Christian Anderson's "The Snow Queen". Tanikumi says Disney copied her autobiography "Yearnings of the Heart" 18 different ways, including a close relationship between two sisters with different hair colors; the main characters living in a snowy place; one sister accidentally hurting the other and having no memory of it; rival suitors named Hans and Christoff; a sister having a "deformity" (Elsa's freezing powers, Isabella's facial scars) that leaves them scared and defensive. Tanikumi even goes so far as to suggest "that writers in the music industry have taken portions of my stories" who "may have corroborated with the writers of 'Frozen'".
This is getting ridiculous! It sounds just like a jealous "unsuccessful" creator wanting to take advantage of a successful one, especially one whose work makes billions. The same thing happened to J.K. Rowling: At least three people filed lawsuits in the early 2010s claiming she "stole" from them to create Harry Potter. Disney had to deal with two screenwriters who claimed it had turned down their ideas for a kid show about an "ordinary" kid who's secretly a singing star, then "stole" them for "Hanna Montana" (aka Miley Cyrus' old show). And this doesn't just happen in kids' media: The creator of a direct-to-DVD movie called "Affairs" sued Tyler Perry and the Oprah Winfrey Network for stealing her movie's plotline--a prominent man having an extramarital affair with a young woman--for the soap "The Haves and the Have Nots". Yes, she wanted screen credit.
I'm sorry, I don't believe it's all about justice--it's all about attention. They are using a "powerful" company to make themselves look like victims to gain sympathy--it's been done before. And it doesn't work: The "big evil company" will never be "brought down", so the "victims" will never "win".
So what is the solution? Get on with life. Keep writing your stories, keep pitching them, and if you can't do it in the mainstream media, find a way to publish them yourself There will always be universal themes in storytelling that will be told over and over in one form or another. Get used to it.