I think you misread the post... He's saying try to get their kid to sleep in their own bed throughout the night (as opposed to any number of alternatives, not

I think you misread the post... He's saying try to get their kid to sleep in their own bed throughout the night (as opposed to any number of alternatives, not just co-sleeping) led to a dramatic increase in his stress level, which may have influenced his development of an autoimmune disorder.