I've noticed that in the back of my four yr old sons throat, the dangling thing..uvula?..he has two of them..i thought you are supposed to have one

Natural variation: A bifid uvula is a normal variation and it can look like having two. No need to be concerned.

?submucous palate: A bifid uvula (double uvula) may be a sign of a small amount of misalignment of muscle in the palate. Although it may be superficially normal (and could be completely normal), there is a possibility that there could be a small area of missing muscle called a submucous cleft palate which may affect speech. This should be evaluated by a specialist to be sure.