OK....
I read through some responses...
First
YES CONSTIPATION IS A HEREDITARY ISSUE!!!
Usually it is most common in males.
There are so many reasons for hereditary constipation...
Lets give you some good information first..
The large intestine is not for digesting, it balances fluids, and rids your boy of the wastes. In order for the waste to pass freely, your colon needs to draw fluid to move it smoothly. In adults, polyps and other lining anomolies will interfere with passing waste. In children, it is primarily a fluid or neurological issue. I am saying neuro, not mental. When teh waste does not pass, it builds up much thicker than the smaller sphincters of the rectum are acustomed to, and you will see bleeding and severe discomfort passing these large stools. When they are not passing....the waste must go somewhere. Usually it is not a complete obstruction and instead of constipation, it appears to be diarrhea. What is happening is; some of the stool is liquifying behind the obstruction and seeping out around the blockage.
Fluid
Abnormally small ureters in tend to cause constipation in children. Especially males. This type of growth anomoly is usually hereditary.
Neuro
Having a lack of nerves to cause the bowel movement needed to move the stool along the large intestine will cause a build up, constipation, obstruction and in severe cases a perforation.
Hereditary disease - Hirschsprung's Disease or HD is the name used for the total lack of nerve growth to the section of colon or large intestine. It is the nerves just stopped growing and it usually detected very young, even just after birth. There is usually a history of downs syndrome or other chromosome disorders in the family.
Sometimes there is a reduced nerve size to the effected segments...caused by a genetic deformity or traumatic injury as an infant. It can cause a decrease in movement, or a decrease in the ability to draw the fluid.
For example, my daughter was born with a hereditary spinal deformity. It was not detected until the GI specialist sent her for an MRI, she was found to have bulging discs and scoliosis. It is so mild, it was never detected in xrays. But that slight misallignment caused her to have abnormally small nerves coming out of her spine in that area and affects her bowel and bladder. She is also incapable of feeling the need to go as strongly as normal people do, so if she feels it a little, she'd better run.
Her colon was incapable of sensing waste and drawing the fluid needed to egest the waste. She was constipated for YEARS. After a doctor found what was wrong, it was amazing how many family members were no longer embarrassed to tell me they had the same problem. After tons and tons of stool softners and laxatives, she was finally given something called Miralax....powdered odorless and tasteless. It makes the colon draw the fluid and poof she was regular! It is available over the counter now.
The majority of females on that side of the family, did not have colon problems...only the males, but had reproductive problems and cervical incompetence causing miscarriages (reason I lost my 4 boys)...and lower back problems. Usually when it is that type of hereditary spine problem, there is a history of scoliosis, spinabifida or more severe birth defects also.
Because there is a small amount of nerve ending, the bowel and colon appeared normal on xrays and the barium xrays. It is purely neurologic.
Do some research in the family medical history. You can learn a lot about the root of the problem. Also ask about hereditary digestive sensitivities...
sensitivity to rye, barley, gluten.....chocolate, high calcium and lactose tend to cause constipation also...
ask ask ask
If you suspect it is caused by a digestive sensitivity...
keep a strict diary of what is ingested...
right down to name brands.
It will help you see patterns.
Good luck!