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 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 Max refuses, she screams for their mother and Max is forced to take her.
While out, they come across neighborhood bullies, and Dani stands up for herself and when she calls Max to help her, she tries to stand for him, but ends up embarrassing him. Max gives them his bag of candy, and they walk away. As they reach another house, Dani says that he should've been braver, but Max gets angry and yells at her for embarrassing him. Upset and hurt, Dani goes off by herself, lies on a haystack, and sobs. Max sits down beside her, apologizes for yelling at her, and explains that it was because he doesn't like living in Salem. Dani tells him that he's just going to have to get used to it, and, with Max's urging, decides to give him another chance. They then enter the house they are near, and learn that it's the home of Max's love interest, Allison. After some talking, the subject comes to the Sanderson Sisters, Max suggests that the three of them go to the Sanderson house, to which Dani is reluctant. While Allison goes upstairs to change, Max convinces Dani to go to the house, making a deal with her.
The trio arrive at the house and Max comes across the Black Flame Candle. Max takes interest in lighting it, to which Dani disagrees. After Max is attacked by a black cat, Dani suggests that they leave, but Max lights the candle, despite her urging. This causes the Sanderson Sisters to resurrect and a fight ensues, ending with Max getting the spellbook and the black cat joining them as they escape the house. They go to a graveyard and the black cat explains Winifred Sanderson'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 witches soon arrive, but are unable to successfully attack the children due to the fact that witches cannot touch hallow ground, which the graveyard consists of. Winifred brings Billy back to help them get the speelbook back, and the children and Thackery go through the sewers and when they emerge, they witness Thackery 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 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. The four of them manage to escape and Max tells Allison to take Dani to her house, but Dani tells Max that she wants to stay with him. After hiding from the sisters one more time, Allison comes up with an idea to burn the sisters 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, Dani promises Thackery that she will always take care of him and that her descendants will do the same and falls asleep, with Thackery sleeping with her. However, the sisters, having survived their plan, retrieve the spellbook, and kidnap her and Thackery, and the sisters prepare to suck the lives out of the children of Salem before the sun comes up. The sisters try to make her drink their potion, but she is able to avoid it long enough for Max to arrive and trick the sisters 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 Billy and he assures her that she will be safe in his open grave, and helps her in. Allison then puts salt around the grave and then the sisters arrive. It starts out with Dani being safe in the grave, but exits it to help Billy get his head back after Winifred knocks it off. Winifred takes advantage of this and grabs her. Winifred 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 Max 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. Winifred again tries to drain him, but she is standing on hallow ground and turns to stone. The sun has come up and Sarah and Mary both explode, with Winifred's statue exploding 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. Dani then says that she loves him, and in response, Max 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 the three children all continue their lives with their families and each other.