Tooley, Adrienne. Betrayal prophecies duology #1

Series title from Goodreads. Duology information from author's website, https://www.adriennetooley.com/ttd

When Elodie and Sabine mistakenly put Velle's young queen, and Elodie's sister, in a coma, they must find a way to wake her before Elodie's siblings learn the truth and Sabine loses her magic--and herself--to the darkness that threatens her if she cannot find an outlet for her sadness

For centuries the citizens of Velle have waited for their New Maiden to return. The prophecy states she will appear as the third daughter of a third daughter. When the fabled child is finally born to Velle's reigning queen all rejoice except for Elodie, the queen's eldest child, who has lost her claim to the crown. To retake her throne, Elodie decides to debilitate the Third Daughter-- her youngest sister, Brianne. She purchases a sleeping potion from the apothecary Sabine, but the vial contains the wrong potion. As Brianne slips into a slumber from which she will not wake, Sabine and Elodie seek to revive the Third Daughter, while a slow-burning attraction between the two girls erupts in full force. -- adapted from jacket

Ages 14-18