 In season 5, Harrison is raised by Dexter, and is watched during the day, and sometimes night, by his Irish nanny, Sonya.It is a frequent concern of Dexter that there will be signs of a serial killer that will point to the baby following in his footsteps.This is seen when the baby inflicts harm on another child similar to how his father cuts his victims on the cheek, and when his repetition of the phrase "Bye-bye" sounds similar to "Die-die."