Dani is a free-spirited 8-year-old girl who can be volatile such as screaming when Max refuses to take her trick-or-treating, but still has a good heart. She is also very brave, as she can stand up to the neighborhood bullies and fight against The Sanderson Sisters. Although she can argue with Max, she clearly still loves him, as shown when defending him from Winifred and refusing to leave his side when he tells Allison to take her to safety.
Role in the film
Dani is first seen in Max's closet, giving him a scare. She then tells him that he has to take her trick-or-treating that night, as their parents are going out. When he refuses, she screams for their mother and he is forced to take her.
While out, they come across the neighborhood bullies, Jay and Ernie. Dani stands up for herself and when she calls Max to help her, she tries to stand for him, but ends up embarrassing him. He gives them his bag of candy, and they walk away. As they reach another house, she says that he should've been braver, but he gets angry and yells at her for embarrassing him. Upset and hurt, she goes off by herself, lies on a haystack, and sobs. He sits down beside her, apologizes for yelling at her, and explains that it was because he doesn't like living in Salem. She tells him that he's just going to have to get used to it, and, with his urging, decides to give him another chance. They then enter the house nearby, and learn that it's the home of his love interest, Allison. After some talking, the subject comes to the Sanderson Sisters, he suggests that they go to the Sanderson cottage, to which Dani is reluctant. While Allison goes upstairs to change, he convinces Dani to go to the house, making a deal with her.
They arrive at the house and Max comes across the Black Flame Candle. He takes interest in lighting it, to which she disagrees. After he is attacked by a black cat, she suggests that they leave, but he lights the candle, despite her urging. This causes the Sanderson Sisters to resurrect and a fight ensues, ending with him getting the spellbook and the cat joining them as they escape the house. They go to a graveyard and the cat explains Winifred's one time lover, Billy Butcherson. Through this, Allison realizes that the cat is Thackery Binx, a teenager who mysteriously disappeared the day the sisters were hung. He then tells them of his failure to save his sister, Emily, and what he spent the last 300 years doing. The sisters soon arrive, but are unable to successfully attack the children due to the fact that witches can't touch hallow ground, which the graveyard consists of. Winifred brings Billy back to help them get the spellbook back, and the children and Thackery go through the sewers and when they emerge, they witness him being resurrected after getting hit by a bus, as his immortality keeps him alive.
They try to warn what they believe to be a police officer, unaware that it's just a costume. When he doesn't believe them, they go to the town hall to warn Max and Dani's parents. After they have a hard time convincing them, the sisters arrive and cast a spell on all the guests to dance until they die, all the while Billy arriving at the scene, where they again run from him. They manage to escape and Max tells Allison to take Dani to her house, but Dani tells him that she wants to stay with him. After hiding from the sisters one more time, Allison comes up with an idea to burn them to death, which seems to be successful and they cheer. Dani then tells Thackery to come home with them, adopting him as her cat. At home, she promises him that she will always take care of him and that her descendants will do the same and falls asleep, with him sleeping with her. However, the sisters, having survived their plan, retrieve the spellbook, and kidnap them, and they prepare to suck the lives out of the children of Salem before the sun comes up. They try to make Dani drink their potion, but she is able to avoid it long enough for Max to arrive, trick them, and save her and Thackery.
Max, Dani, Allison, and Thackery then return to the graveyard in Max and Dani's parents' car, where they come across Billy again, and Max tells her, Thackery, and Allison to go on while he deals with Billy. When Max catches up to them, Billy is with him and he tells them that he's on their side. Dani then greets him and he assures her that she will be safe in his open grave, and helps her in. Allison then puts salt around it and then the sisters arrive. It starts out with Dani being safe in it, but exits to help Billy get his head back after Winifred knocks it off. She takes advantage of this and grabs her. She tries to force her to drink the potion, but it is knocked away by Thackery, who is then knocked off and falls to the ground after hitting a rock. Max, having caught the potion, drinks it to save her. While he tries to hold off Winifred from getting his life force, Dani, Allison, and Billy manage to hold back Sarah and Mary and cause them to fly out of control, which distracts Winifred, and Max knocks her and himself to the ground. She again tries to drain him, but she is standing on hallow ground and turns to stone. The sun comes up and Sarah and Mary both explode, with Winifred's statue doing so afterward.
Dani goes over to Max's side and says that she can't believe that he did that for her. He says that he had to, being that he's her brother. She then says that she loves him, and in response, he says that he loves her too and they hug. The two of them and Allison thank Billy for his help and he returns to his grave. Dani then finds Thackery's body and begs him to wake up, and sobs when he doesn't. However, his ghost comforts her. He says that he will always be with her and kisses her on the cheek and she watches tearfully as he leaves with Emily.
Max comforts her and they all continue their lives with their families and each other.