Queen Leah is shown to be a caring individual and a loving mother to her daughter, Aurora. She is shown to love her family.
In Descendants, she is initially friendly toward Mal until her granddaughter Audrey informs her of Mal being the daughter of Maleficent, causing Leah to (unfairly) unload her loathing of Maleficent for causing her to miss out on her daughter's entire childhood onto Mal (and unknowingly help Mal realize the pain of others), which spurs Mal angrily back to her mission of gaining the Fairy Godmother's wand.
Queen Leah and her husband are the monarchs of an unnamed kingdom, in medieval Europe. After many years of marriage, she gives birth to a beautiful baby daughter which she and her husband name Aurora, after the goddess of dawn. Her happiness is shortened when Maleficent, who was not invited, curses her daughter. Devastated, she has to see her daughter taken away by the fairies in order to protect her. Sixteen years later she is waiting for the return of her daughter, but when Aurora touches the spindle, the Queen and the entire kingdom are put to sleep by the Good Fairies. When Maleficent is defeated she awakens and is finally reunited with her daughter, whom she embraces and cries tears of happiness when she sees her.
In the short segment, Stefan, Leah, Hubert, and Phillip all go off on a royal ceremony where Hubert is due to give a speech. Trusting their daughter, Stefan and Leah give Aurora the "keys to the kingdom" while they're away.
In the ABC fantasy drama series Once Upon a Time, she's called Briar Rose (as a reference to Sleeping Beauty). The original Sleeping Beauty, she had incurred Maleficent's wrath, and was cursed by her into an eternal sleep before King Stefan awakens her with true love's kiss. While Maleficent falls into ruin, destroyed by her failed revenge, King Stefan and Briar Rose marry and have a daughter named Aurora. Years later, when their daughter is set to wed Prince Phillip, King Stefan seeks to get rid of Maleficent permanently to keep Aurora safe from her. Instead, Maleficent regains her lost ability to morph into a dragon and gains the upper-hand over the king, but the latter managed to survive. Later, Maleficent gains retribution against Briar Rose by cursing Aurora into an eternal sleep.
Queen Leah appeared in the film under the name of Leila and was portrayed by Hannah New. She is the daughter of the ruthless King Henry. She remains loyal to her father who performs her duties as a princess by becoming Stefan's wife and later bearing his child. She would soon witness Maleficent, her husband's former friend whom he betrayed would place a curse on her daughter Aurora.
During the course of the film, she becomes gravely ill and eventually dies. Stefan shows no grief over her death as he has become paranoid and obsessed with hunting Maleficent down.
Queen Leah appeared in the Disney Channel Original Movie played by Judith Maxie. By that time she is a grandmother to Audrey. She is shown to be apathetic toward the villains, but especially Mal in particular, because her mother caused Leah to miss out on her own daughter's entire childhood. After the incident at the coronation, she appears to have accepted Mal and the others; she observes as Audrey thanks Mal for stopping her mom.
Queen Leah attends an announcement made by Ben, and watches him ask Mal to be his queen. She chides Audrey for not being able to win Ben over, stating that Aurora managed to hold onto a prince in her sleep. After Audrey is defeated by Mal, Leah watches Hades awaken her from a deep sleep, and apologizes to Mal. She later claps as Mal declares that the Isle's barrier will be taken down.