No, not the child. You! In most cases you want the camera to be at the same level as, or just a little above, the eyes of the child. In addition to making the expression more natural it’s also more relaxing for the child, if that stranger of a photographer is not staring down from high above through a huge lens. Sit down on a chair or on the floor to fit the level of the child, but don’t go down too much. If you make a person look down the face is “squeezed” together creating double chins and smaller eyes. You don’t want that. Some people tend to close their eyes a little when smiling. When this is the case you should make them look up a little. Go higher but not so much that it’s obvious that the photo is taken from above. When people look up the visible part of their eyes gets bigger, even when they are smiling. And as mentioned earlier, the eyes are of great importance to the portrait, so you want as much eye as you can get.