Yes, a recent complaint from my  4 year old son about sore teeth, took us off to the dentist.  We were blown away that the dentist said there was too much work for someone so young to experience - he needed to see a Paediatric Dentist who would have a look at Carters teeth, and probably put him under at a local Private hospital to work on him.  

Yes he had 6 holes in his teeth, that had grown considerably deep.  And in the end, had them not only cleaned up and filled - but also have stainless steel caps put on them all. Overall a $2000+ experience.

Learnings - make sure you clean your childrens teeth as soon as they come out and keep it up morning and night. (It isn't all because of this, but also due to no fluoride in the water here and the make up of his teeth, having deep natural cavities).  Honestly, We casually started cleaning Carters teeth (i.e. not every day) when his had a number of teeth and the once a day when he was two onwards (but most of the time we let him clean his teeth - which we have since learnt we should have cleaned them a bit longer with him and taught him longer.

(p.s. have to say if you are in the Gold Coast - Dr Michael Chong was very good)