Given the following context:

One evening, after getting drunk at a bar, Mitch and Dave urinate in a park's fountain, and simultaneously wish that they had each other's lives.
The next morning, Mitch and Dave realize they have switched bodies. Mitch remembers the wish they made the night before and they drive back to the park, planning to urinate again in the fountain and wish for their original lives back, but find the fountain has been removed for restorations. Forced to wait a few days until the parks department can locate the fountain, Mitch and Dave agree to pretend to be each other for the day. When Mitch arrives at Dave's law firm office, he befriends Dave's attractive assistant, Sabrina McKay.  However, Mitch's lack of professionalism and legal knowledge cause a big merger to fall through. Meanwhile, Dave arrives at Mitch's film shoot to discover that it is a lorno (light porno).
Tired of pretending to be Mitch, Dave has them go back to his house to tell his wife Jamie the truth, but Jamie does not believe him. Dave gives Mitch advice on how to behave professionally and Mitch sets Dave up on a date with Sabrina, who Mitch has had a crush on.
After speaking with his father, Mitch rededicates himself to doing everything Dave's life demands, from taking care of the kids and buying groceries to making decisions at the firm. On the night of her ballet recital, Cara, Dave's eldest child, is about to be pushed by another girl who has a habit of bullying her, but takes Mitch's advice and throws her to the floor, to which Mitch foul-mouthedly cheers. Cara tells Mitch that she loves him and Mitch says the same thing, but feels guilty for doing so immediately after. That night, Mitch and Jamie begin to have sex with each other, but Mitch angrily finds that his guilt will not allow him to become erect, and he admits that he is not cut out for the responsibilities of an adult. Jamie comforts him, and he discreetly rests his head on her breasts.

answer the following question:

Who tells Dave's oldest child to throw her bully to the floor? 

Mitch