My friend's child drinks only fanta grape cool drink mixed with little water, Is that unhealthy?

I consider it so. This is just flavored sugar water. It has no true benefit to a child's nutrition from this, most juices, or similar products.If you want to pattern a kids brain to crave sweets or sugar, you let them do this.If you want them to use sweets sparingly and avoid the weight issues involved, you give them water.