There are alot of variables here that I'm not aware of. Was the child nursed? How was the mother's diet? What is his diet? Are there any other health problems? What are the mother's bowel movements like?
Let me share some general experiences, which might be better anyway, because then we are not talking about a specific child.
One day soon I will share the entire experience of how I ended up leaving the Philippines with a 2-month old baby at the age of 50 - but, for now, let me share some of the challenges I faced when she was given to me at the age of 1 month.
I had gone to visit a couple of orphanages in the Philippines to see if my teenage daughters could do some volunteer work. At one of the orphanages, there was a 1-month old baby girl with multiple problems who weighed less than 4 pounds. Because of what I do, I shared some ideas with the lady who owned the orphanage on some simple things she could do to help this child. When I got ready to leave, she handed me the baby and said, "Why don't you take her home for a week and see if you can help her?" So, naturally, I did.
As I was leaving the orphanage, I asked the lady what she had been feeding her, so that I could get the same thing and not upset her system worse than it already was. The lady said, "Oh, you would never feed her what I have to feed her. Due to lack of funds, I can't give her much more than sugar water"!
Needless, to say, it's not hard to see why this child was 'a failure to thrive'. Anyway, one of the first challenges I faced was that her bowels never moved on their own. I tried several different formulas (only because this was all I had access to) only to find that she could not digest any of them properly. The only way she had a bowel movement was for me to use glycerine suppositories or to apply castor oil to her abdomen and cover it with hot (obviously not hot enough to burn), wet wash cloths. In doing this procedure - I liberally apply the castor oil over the intestines, then I use a wet, warm wash cloth to lay over it. Every 5 minutes or so, I put my fingers under the cloth to see if the skin is still oily - if it's not, I apply more castor oil. I do this for about an hour. This allows the body to absorb the castor oil which softens the stool and stimulates the peristalic action.
Whenever, she did have a bowel movement it was tarry, black and green - as though she had never fully eliminated the meconium (new-born baby tar - the packing material). We did this for a month until I could get her back to the 'states'. One of my daughters had a healthy baby boy three weeks early on April 6th - we landed on April 8th. When we arrived home, I took my baby to see a pediatrician friend of mine. He examined her and then sat me down to prepare me for the fact that she would not live. She had too many problems due to mal-nutrition. I immediately put my baby on my daughter's milk. For 4 1/2 months my daughter fed both babies - she nursed hers and pumped for mine. I poured nutrition into my daughter - green drinks, anti-oxidants, minerals, vitamins, oils, etc. Both babies thrived! After the first 48 hours on my daughter's milk, my baby pooped out the most beautiful yellow, mustardy baby poop I had ever seen all on her own!
The moral to the story is - nutrition, nutrition, nutrition. I would make sure the diet was full of fresh fruit juices (maybe even add some prune juice in the beginning), fresh fruit and vegetables, no dairy (unless it was fresh goats milk with the live enzymes still intact), no meat, the right fats (either in olives, nuts, avocadoes, or an omega 3/6 supplement) and even a 'green' drink once a day. My grandchildren and daughter love when I take fresh pineapple juice, a banana, add some ice and a TBSP of green powder or fresh wheat grass juice - blend it up and have green smoothies.
Many children today live on almost 100% processed foods - it's no wonder they can't poop! There are no live enzymes available to help them break down their foods. Another problem is inactivity - children need to be children - they need to run and play, which also helps to stimulate the lymphatic system and encourage peristalic motion. Children were never meant to sit idle - watching television, computers, or being kept busy at a desk. No child should go more than 24 hours without a bowel movement. In fact, ideally, they should have a bowel movement after every meal - not diarhea, but a normal soft bowel movement. In with the new - out with the old!
Hope this helps, Dr Mom