I guess that's another question I have. Ideally on one ticket. I can get a ticket for her using my Avios on BA.com at the moment, but only one seat available so that could disappear anytime. That covers HKG - BDA.

I've looked at just buying her a ticket from HKG - BDA and the only way I can do that is through Expedia, which charges almost $5k for one way in economy.

If I break the two of them up, and purchase the first flight on Cathay and the second on BA, I can get it for a total price of $1,800, but that leaves open the possibility of bags not being checked through.

Is there a smarter way to book this flight using both Cathay and BA? I tried BA.com itself. As I said above, it works when there are mileage seats available, but the only revenue seats it brings up are for connections through the US.