I was going to mention warranty repair (meaning after they charge you to fix it, it stays in warranty) but...you took it apart.
The manufacturer may sell parts, or link to a service company that will sell you parts. It's going to cost you though, and may not be worth repairing depending on the age/speed of it. Sometimes cheaper to buy a new one.
I just realized you may be more concerned with keeping your sister from noticing that you let a chicken destroy her thousand-dollar or more computer that may or may not be extremely important to her life. Not much help there unless you can fix it really quick. 🙂