How can I become a pediatric nurse?

Depends what hospital. I just graduated from a 2 year program. Few people got a job at childrens hospital in pittsburgh which I think is one of the better hospitals in the country as a Graduate Nurse. So no, I wouldn't think so. Doesn't hurt to ask a hospital in the area. It's not like a law or anything though. It's just where you work. Some Operating Rooms want certificates beyond nursing school. Besides that and masters programs I can't think of anything that requires formal extra training.