I'm not sure what to do

Where I live no dentist will see a child before they're three (that's what I've been told but my friend has taken her daughter since she turned one) I've called every dentist in the area they refuse to see my son and he has had a mouth full of teeth since he's been 10 months old. He's now two, he has a really bad cavity on one of his top teeth and they still will not see him! I'm not sure what to do. I'm worried because bad teeth runs in our family, my sister had to get dentures at 30, my mom got them at 47, and I have always gotten cavities very easy. I just don't want his teeth ending up like ours. I'm seriously freaking out.

*i even called the place my friend takes her daughter and they told me the same thing, that they wouldn't see him until he's 3. Which I don't understand because my friend takes her daughter and she won't even be two until January. My insurance doesn't say anything about having to wait a certain age, and I asked his doctor, she also said that most dentistry's don't see children until they're 3.