This doesn't make much sense, though. Every additional human is a very expensive investment of time, resources, and effort on the family, and offers no material

This doesn't make much sense, though. Every additional human is a very expensive investment of time, resources, and effort on the family, and offers no material return on investment for at least a decade in terms of productivity. True, while the gay son might not produce offspring to compete with his brother's kids, it also means he brings no additional mate and offspring to help out the family.