I don’t need to tell you that boys and girls develop differently. Parents should be aware of their child’s private parts from the very beginning and should make note of any changes they notice. Then as the child hits puberty, between eight and 13 years of age, the parent should educate the child to be aware of his or her private parts so that he or she, too, can be aware of any changes or problems.

Young girls may develop vaginal problems. Bacterial vaginitis is very common in girls between the ages of two and four. It occurs when bacteria from the skin gets inside the vagina and causes irritation and inflammation. But it’s nothing that proper hygiene can’t prevent. It is important for mothers to teach their little girls how to wash themselves properly.

Vaginal itching is extremely common in young girls. A child with vulvovaginitis, as it is formally known, will scratch her vaginal area or complain of burning or pain when she urinates. Before puberty, the skin around the vaginal area can be very sensitive and become red and inflamed by a number of common irritants. One of the most common is soap or shampoo.

A lot of young children take bubble baths, and parents tend to forget to rinse them properly after they sit and play in the soap suds. Another common reason is poor toilet hygiene. When toilet training young girls, parents must also teach them to wipe after urination, which sometimes they forget to do in all the excitement over their success in having them sit on the potty. On the other hand, excessive wiping after urination can also cause irritation and itching.

In rare cases, vaginal itching can be associated with pinworms, which look like small pieces of thread and are about a quarter of an inch long. Usually pinworms cause itching around the anal area, but they can also manifest in the lower vagina. Pinworms tend to cause symptoms at night when they migrate out of the anal area. If recognized, pinworms are diagnosed very easily with fecal cultures and are easily treatable. See your doctor for this.

As young girls approach the age of eight or nine, vaginal itches may be caused by vaginal yeast infections. Yeast is a natural flora of the vaginal mucosa, but when it overgrows, it can lead to an inflammation, causing burning, redness, and irritation, and it may produce a thick white discharge. There are many reasons for the overgrowth of vaginal yeast. The routine use of antibiotics, which may occur in children with frequent ear infections and throat infections, can lead to the overgrowth of yeast in the vaginal area. Poor hygiene, again, can be another reason.

Even a small piece of toilet paper left in the small vaginal orifice can cause an infection and vaginal itching. A diaper rash in infants and toddlers may appear not only in the buttocks and anal area, but also in the vaginal area, and that could also be attributed to an overgrowth of yeast. Most of these problems are easily treated either by a primary care physician or by a pediatrician.

Urinary tract infections are, of course, a recurring issue for women during their entire lives. The reason why women get more urinary tract infections is because the tube that connects their bladder to the outside, called the urethra, is very short. This means that bacteria can make their way into the bladder fairly easily. Males don’t have this problem as often because the penis provides them with a longer urethra.

Girls can also have something called bladder reflux, in which the urine flow from the bladder backs up into the tubes called ureters, instead of flowing normally down from the kidneys, through the ureters, to the bladder. This problem is commonly diagnosed in children who have had a urinary tract infection. The infection can cause a blockage in the urinary system, which then leads to a swelling of the ureter.

Males, on the other hand, may experience problems with their testicles. One is varicoceles, which is essentially a varicose vein within the testicle. It’s caused by a damaged valve in the vein, draining blood from the testicle. There is nothing that can be done to prevent it, and there is no treatment, although if the boy is uncomfortable, he may need to wear supportive underwear.

Then there is testicular torsion, which may occur beginning at the age of eight or nine. The problem causes an acute severe pain of the testicles, or sometimes just a dull pain. Testicular torsion is a twisting of the spermatic cord that holds each testicle suspended within the scrotum. When the cord becomes twisted, it can cut off the blood supply to a testicle. If it is not treated quickly (within hours), the boy could lose a testicle; an operation may be needed to untwist the cord. There is no known cause for testicular torsion, but it can sometimes result from physical activity.

A third problem are inguinal hernias, which are basically weaknesses or tears in the wall of the groin. Though not confined to boys, boys will experience inguinal hernias about ten times more frequently than girls. Symptoms include pain, nausea, blocked bowels, and a bulge in the groin area, which can extend to the scrotum in boys, that remains even when lying down. Surgery is usually necessary to repair the hernia.

Both girls and boys are subject to precocious puberty. This occurs when signs of puberty appear prematurely—with breast development and the onset of menstruation in girls before age seven or eight, or with the enlargement of the testis and penis and facial and pubic hair growth in boys before the age of nine.

When it occurs in girls, there is usually no underlying medical problem, though there may be one in boys, in whom the condition is less common but may be hereditary. Hormones in food, especially hormone-grown poultry and beef, may cause early development in girls, according to some reports.

Precocious puberty can be physically and emotionally difficult for children. It’s important that parents provide a supportive environment for the sexually precocious child, explaining that these changes are normal for older kids and teens, but that his or her body has started developing a little too early.

Click here to check out Dr. Manny's book The Check List (Harper Collins, 2007), from which this article was excerpted.

Dr. Manny Alvarez is the managing editor of health news at FOXNews.com, and is a regular medical contributor on the FOX News Channel. He is chairman of the Department of Obstetrics and Gynecology and Reproductive Science at Hackensack University Medical Center in New Jersey. Additionally, Alvarez is Adjunct Professor of Obstetrics and Gynecology at New York University School of Medicine in New York City.

Dr. Manny Alvarez serves as Fox News Channel's senior managing health editor. He also serves as chairman of the department of obstetrics/gynecology and reproductive science at Hackensack University Medical Center in New Jersey. Click here for more information on Dr. Manny's work with Hackensack University Medical Center. Visit AskDrManny.com for more.