What is common in infancy
It is common for a baby's eyes to turn in or out too much at moments in the early months. In most cases they become steady and straight as the child grows older. If, however, the eyes turn in or out all the time or much of the time, even in the first months, or if they are not steady by 3 months, an eye doctor should be consulted.
Many times parents think their baby's eyes are crossed when they are really straight. This is because the skin area between the eyes is relatively wider in a baby than in an older person; so the amount of white of the eye showing on the inner side of the iris is much smaller than the white on the outer side (toward the ear).
Another reason babies' eyes sometimes appear crossed is that when they are looking at something in their hands they have to converge (cross) the eyes a lot to focus on it, because the arm is too short. If you think your baby's eyes may be crossed, you can check the image of a light as it is reflected in the baby's pupils. If the image of the light is always located symmetrically on the baby's pupils, its unlikely that the eyes are crossed.