There are a number of possibilities, so just make sure you know the full situation before making any decisions (get X-Rays).
Sometimes, children will only get one set of teeth. Obviously, in this case you don't want to pull them.
Sometimes the baby teeth just won't come out. I went through this with a fair number of my son's teeth. In retrospect, I think he was timid about wiggling those that became loose, and eventually some were wedged in by the eruption of the permanent teeth underneath.
Those teeth, then were safely pulled, and the "adult" teeth moved in to position normally.
You just never know... My son actually grew THREE teeth in one spot (rather than just the normal two), and my daughter has one empty space in her mouth where no baby tooth came in (but the dentist says the permanent tooth is developing normally inside)!