They also arrested 21-year-old Jassman Nicole Smith and charged her with accessory after the fact to murder.
Police say Barber knew Cook.
Shortly before 11 a.m. Thursday, officers responded to a call to check on a resident at the Trestles Apartment complex located on Old Plank Road, just off of Capital Blvd.
They found Cook dead inside her home.
Police say the investigation in ongoing and did not offer any additional details about the cause of death or motive.
Both suspects are being held in the the Wake County Jail.
If you have any information about case, call detectives at (919) 996-3555 or CrimeStoppers at (919) 226-CRIME.