Worked as a dental assistant for 10 years. More then a drink can affect their dental health- Colds, illnesses, other health issues. Drink MILK kids need it! Get electric tooth brushes- much better job on the teeth. Ask the doctor to define cavities and have them show xrays. Some will not show up on the xray. Anywhere you can get a stcik with the explorer tip is a possible area of decay and needs attention to keep it from expanding. Do check on a second opinion and do not tell them what the first doctor said until they have completed their diagnosis. Get a hard copy of both diagnoses and their treatment plan. some docs will say all needs to be done right now others will lay it out in order of what has to be done first and work with the family financially. As to the health of the teet- when a woman is pregnant her own health especially dental will afect the babies tooth buds. Also if there is smoke in the home it is a contributor to their dental issues.