It was so sad reading about your son. I too spent the first two years of my daughters life basically living at the hospital with her too due to what the MTHFR polymorphism caused.. (sacral agnesis/caudal regression syndrome which she had only happens in 1 in every 25,000 live births). Both of my children had/have severe medical issues which were transmitted or caused by my HIDDEN UNKNOWN TO ME at the time issues.. that was even before I got the ME/CFS. What I didnt mention in my other post was about my other daughter. My other healthy looking daughter, she caught HPV from me at birth and needed 16-18 surgeries due to it as it got into her throat and caused Laryngeal papillomatosis and would of blocked her airways and killed her if it wasnt for all the surgery... this issue is EXTREMELY RARE . something like 1 in every 250,000 births and can progress to cancer. Most peoples bodies would fight that off but obviously my daughters didnt so when a young child from what she caught from me at birth (unknown to us at the time)..she then developed all the growths which had to have high risk surgery to remove (every surgery carried a risk to her voice where the growths were of being permently damaged).. so obviously a sign that there is probably something different about the way her immune system functions.. she developed a MAJOR issue from something which most of us carry, her system couldnt fight it of normally at all. (3-4 years of surgery every few months as her body couldnt fight it.. interestingly we ended up solving the issue via taking her to an accupuncturist and geting accupuncture done) She may be TH2 dominant just like I was even BEFORE getting ME/CFS. Something may be faulty in this Th1/Th2 area and hence predisposing some of us to ME/CFS. If HPV is a TH2 dominant illness just like ME is, I believe, due to what my daughter has already experienced as a child with that.. .. I must of already passed the same hidden immune defect or whatever causes the TH2 predominant state be it a virus or otherwise.. down to her, which would predispose her also now to developing ME/CFS. For more on TH1/TH2 and ME read Dr Cheney's take on this @ http://www.anapsid.org/cnd/diagnosis/cheneyis.html So sadly..not just one but BOTH of my kids ended up with SEVERE issues caused by my genetics.. with the one child being unfortuntely also being hit with the Aspergers as well as the rare caudal regresssion syndrome. So its hard not for me to believe what Ive heard said by well known ME expert that they often see rare issues in the children of those who have ME. Of cause it is possible to have healthy children too, its really like a game of dice. (note Im talking about ME cases and not general CFS cases.. those who arent of the ME subgroup of CFS probably dont have to worry much about transmitting issues to children and polymorphisms etc etc) edit. I just noticed that the poster after me mentions she had a "failure to thrive" child.. I didnt mention it but my non Aspie child who had the HPV growth issues due to some unknown immune disorder, was a failure to thrive child too (completely unrelated to the other thing). She had to spend a whole week in hospital while doctors tried to work out why she wouldnt eat but they were unable to work it out. (she was like a 2 year old with annorexia). She ended up being put on dangerous meds (i think it was steriods) to force her to have an appetite and she had to be put on a very special diet. At 3 years old.. she only weighed like what an 18mth old usually weighs (she developed the issue at about 16mths old and from there didnt put on weight)... she was basically starving herself. Fortunately her eatting issues and whatever reason was behind that, were gone by the time she was 4 (but then a few years later she then developed the other issue needing constant surgery). I also didnt meation that I almost lost my other daughter (the Aspergers one) at 6 weeks old.. what they called near miss cot death.. She suddenly heamorraged from nose and stopped breathing and had to be resusitated back with CPR. (I only have the two children.. but both had multiple severe issues). Doctors too couldnt work out what caused that issue at the time.