Originally Posted by
Eclipsepearl
Not true. Most of us with two passports use one for one direction and the other for the return. They don't have to match at all. In fact, I'm supposed to "mix them up".
Well, whatever you say, but my wife is US/UK dual and once got a terrible chewing out for "mixing them up" on a US-LHR-JNB trip. I am always inclined to keep things simple, especially when kids are traveling on their own.