A buried penis is medically known as an invisible penis. Nine-year-olds can be judged by observing the appearance of the penis, checking hormone levels in the hospital, and ultrasound of the penis. Generally speaking, if a nine-year-old child has a hidden penis, the development of the penis itself is normal, but the penis will be buried in the foreskin and the pubic bone area subcutaneous fat tissue, the appearance of the penis is short, and the distance between the opening of the foreskin and the root of the penis is short, and the penis can be seen by pushing the foreskin to the root of the penis, and the penis body will retract rapidly after releasing it. Generally hidden penis is mostly seen in obese children, and in appearance and short penis has some similarity, usually by oneself is more difficult to distinguish, therefore, it is recommended to have the above situation, go to the hospital for hormone levels and ultrasound examination of the penis, with the help of the doctor to make a comprehensive judgment. It is recommended not to make a blind judgment on your own, so as not to make a wrong judgment. If diagnosed after examination, you should actively cooperate with the doctor for treatment, and at the same time control diet and strengthen exercise to relieve the symptoms of obesity.