When I worked for an airline in early 2000s, I don't recall what the exact rule was but I never encountered a child international traveler who did
not have their own passport.
A question in light of the fact that the two Sussex offspring are now scheduled to travel from the U.S. to the UK: since the UK does in fact issue "Child Passports", but the U.S. does *not*, does it not also mean that: (a) When Lilli M-B was born in California, her father would have had to have registered her birth at the nearest British consulate as a "child born abroad of a UK subject"? Which in turn allows her to travel solo now with her grandmother into the UK? And then (b) One wonders how these two children have traveled on previous travel outside of the U.S., since in fact they also qualify for American citizenship? So, were they previously on Markle's passport until now, or did they always have British "child passports" of their own? All very murky, but very convenient when you want to claim a princely title for your children isn't it?
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