It's true that heat and humidity can be very beneficial to some forms of Ichthyosis. However, some forms of Ichthyosis are very heat intolerant, like your son's EHK. I don't think the benefits of the heat and humidity would outweigh the overheating and plain misery that comes with it for me. Something else to consider, I talked to a couple at the last conference who adopted a child with Ichthyosis from Singapore. Their description of how the public in Singapore treated their child, whether it was ignorance or cultural, regardless, was absolutely horrible. Should you decide to move there, the hot weather will be only one of your biggest problems.