Well first make sure your 3 yr old brushes his teeth everyday. If he doesnt brush his teeth then that's why he has yellowish teeth.
looks like what you would expect booth teeth yellowish
Brush them...with toothpaste.
Yellow teeth will maintain the same shape and form as white teeth, but unlike white teeth, they will have a dull yellowish-amber tinge to them.
Coco-Cola will make your teeth become kinda yellowish-brown if the soda touches your teeth too much...I suggest you use a straw
you drink to much lemonade
yeast infection
Enervon C has mercury.
Healthy teeth should be white. If you have a lot of sweets and don't brush your teeth often you could have unhealthy teeth and get lots of cavities. Also, if you smoke you get yellowish teeth and should probably go see a doctor.
Tooth bleaching is recommended when someone has yellowish, but otherwise undamaged teeth with no particular sensitivities. The teeth should also be free of orthodontic devices such as braces.
lack of calcium in your body causes white stripes on teeth and nails.
missing teeth