My son did the same thing. He will not drink milk from a glass, but he did from a bottle. He's 5, and he's healthy. Don't worry, there are plenty of other good sources for calcium. Some that you may want to think about are fortified breads, bunches are made now fortified american cheeses, cereals, juices, even snacks have calcium added. If your son likes yogurt, there are lots of kid style yogurts out there. Personally, my son hates anything creamy, so he does not eat yogurt. You also have to keep this in perspective, as far as his requirements. According to the USDA, the daily requirment for a healthy child your son's age is about 500 milligrams of calcium a day. A grilled cheese sandwich has about 500 to 600, if you use a calcium fortified bread and calcium fortified american cheese. When you are looking at the packages, when it says 30 percent of the daily requirement, it means that there is 300 milligrams of calcium, because daily requirements are listed for adults, not children. Other veggie sources of calcium are broccoli and spinach. Don't ever feed your child calcium supplements. They can lead to digestive problems and kidney problems. Hope this helps, and hope you can relax.