Pediatric Doctor(pediatrician) vs. ER doctor?

ER doctors are basically doctors that work in the emergency room, thus ER, they know a lot of information on what to do for things ranging from the common cold to serious gun shot wounds. a Pediatrician is someone who specializes in children, there are pediatricians who work in the ER, if the child is stable he may only see a pediatrician however if he is in critical condition more then one doctor may be attending to him/her.