> The twin who remained in South Korea was raised in a more supportive and cohesive family atmosphere. The twin who was adopted by the U.S. couple, in contrast,

> The twin who remained in South Korea was raised in a more supportive and cohesive family atmosphere. The twin who was adopted by the U.S. couple, in contrast, reported a stricter, more religiously-oriented environment that had higher levels of family conflict. This part is unsurprising to me. Religious upbringings can, and do, cause emotional trauma which can lead to problems with mental and physical health, which affects cognitive ability. It's not a problem with the individual interpretation of a religion, but with the ideology itself, which insists that bronze age moral standards should apply in today's world—including those based around blood sacrifice. The real tragegy is that many consider it good parenting to raise their children to be religious, even if they aren't religious themselves.