Chelsea's friend, Nova, had epilepsy which was causing seizures that were so frequent that Derek Shepherd decided to do a hippocampectomy to treat her. With his busy schedule, he kept having to reschedule. When he came into Nova's room one night, Chelsea yelled at him, saying that it was cruel to keep rescheduling Nova's surgery because she kept having more seizures and she hadn't eaten in two days. He insisted that the surgery would happen that night, in the middle of the night.
The surgery was performed. While assisting Dr. Shepherd, Leah Murphy made a mistake that could have caused permanent brain damage. After surgery, Nova was reluctant to wake up, but she ultimately opened her eyes and spoke.
She is very outgoing and insistent, the opposite of Nova, who is shyer and more reserved. As such, Chelsea stood up for Nova when her surgery kept getting pushed back.
She is best friends with Nova Jenkins. Chelsea accompanied her to the hospital and stayed while she had the surgery.