Oscar is the baby of Dana Barrett in Ghostbusters II. When the infant was first examined for any type of paranormal traits, Egon Spengler confessed the only near-pediatric experience he had to this point was on a young chimp.
Oscar has the same personalities as all babies. He appears to be very calm when in the presence of his mother and her friends. He is also very frightened of Vigo, as evidenced by his constant screaming.
His last name was never revealed in any source about Ghostbusters, but fan sites have been known to give him the last name Wallance (After Andre Wallance which is the birth father) and later as Venkman (after Peter Venkman, who marries Dana after the movie). However, none of this has been proven in official Ghostbusters Canon. In the novel he was referred to as Oscar Barrett.
- Dan Aykroyd said that one of his rejected scripts for Ghostbusters III had Peter going on a second honeymoon with Dana, and that the rest of the Ghostbusters were to keep an eye on Oscar, who would have been in his early to mid teens. Oscar would become a junior member of the team. In a recent interview, Sigourney Weaver mentions that in a copy of the script she read, Oscar does join the Ghostbusters.