Generally speaking, the vision of the children and youth will progress because the development of their eyes are not completely. Moreover, eyes over-used and too much schoolwork are also the causes. However, as the growth of the age, perfect eye development, plus reading less, so myopic degree is stable. However, if staring excessively at a computer for a long time , the degree of myopia will progress. So please protect your eyes at any age, which is most important.
Actually, when we are the six-month old baby, our vision developed as 20/20. That is to say, when we are 6 month old, we have got the normal vision and our vision has been stable. However, strictly, from then on, if you do not use your eyes correctly or you overuse your eyes, which will cause eye fatigue or eyestrain. Further, it will affect your vision, you will get nearsightedness or farsightedness. Strictly speaking, our vision will not get stable only if you use your eyes correctly and well protect your eyes. Hope this helpful.