While bedwetting is more common in younger children, it's not unheard of for a 14-year-old to still experience it, although it occurs less frequently than at younger ages.
The provided reference indicates that bedwetting, also known as enuresis, is a common medical problem among individuals under 18. While many children outgrow it, this is less likely to occur without treatment, especially in teenagers and those who wet the bed frequently.
Because the provided document did not list prevalence, I cannot provide an exact answer to the question of commonality.
