A.E.
Hi, H.,
My daughter, who is now almost 4, also has some tooth decay on one of her front teeth (I noticed it first when she was about 2). The pediatric dentist has no idea why...all of her other teeth are perfectly fine and healthy. They say it could have started in utero. In any case, because they don't loose those teeth until the age of 6 or even 7, they recommend filling it. I'll be taking her in a few weeks to get it filled, so let me know if you want to know how it goes!
Good luck,
A.