Terrible, and I don't mean to be offensive, but there's something I don't understand

Hawaii girl, 3, dies after dental procedure

Finley's mother, Ashley Boyle, said she first took her daughter to the dentist in November, when she was told her daughter needed six fillings and four root canals, she said.

Why would a three year old need root canals? Granted, I don't know much about dentistry, but that seems odd. I mean, doesn't that kill the nerve there? And with a child that young, there's teeth below to still come up, right? Still, it's horrible that the girl died, whether from negligence or some freak occurrence.