Looking for 4 economy award seats on CX JFK-YVR flight, for 1 adult, 3 kids. If 2 seats are showing available on BA, is there a way to book now for the adult + 1 kid? Would there be an issue in future when 2 more seats open up, since BA won't allow two kids (under 16) to be on their own booking, since it will technically be as unaccompanied by adult? Any workaround for this? Thanks