Your original statement - that a carbon-hedonistic lifestyle of frequent flying and cruise ships would still be lower CO2 output than having children - is flatly wrong, and your source does not bolster your argument.
Sure, but who's to say whether or not those children will fly on planes or go on cruises? Or their grandchildren? Or their great-grandchildren? This strikes me as a fallacious argument that simply not going on cruises or plane rides can offset the environmental footprint of having children. At least not unless there's some mechanism to forbid those children from every flying on a plane or taking a cruise - and not aware of any such mechanism.
