Milage to Australia

[eliraps]

We are a whole family flying from London to Australia with Cathay Pacific. (The way there is class V, the return is class H).
What is the best thing to do with the miles?
Put them on an AA advantage account? (Which would mean opening and starting an account for everyone).
Open a Cathay Pacific account?
Is there a way to post all the miles onto 1 account?

[steve2]

 BA has a family plan which would join all the miles of everyone together if you open a family acct (not sure I think its 4 people max) same address.

 But then youd have to put up with BAs T&Cs but youd get award tkts alot faster but alot better then maybe losing them , also BA is activity once every 3 yrs, AA is every 18 months CX I dont know

[Dan]

It appears that AA gives 100% credit for H fares, but nothing for V fares.  So credit for the return flight should be made to AA:
http://www.aa.com/i18n/AAdvantage/partners/airlines/cathayPacific.jsp

As for the outbound flight, it looks like you can credit a V fare to Asia Miles and get 100% credit.
BA only gives 25% credit for V fares:
http://www.britishairways.com/travel/ecpartnroneworld/public/en_us

LAN may be your best option with 100% kilometers credited for V fares:
http://www.lan.com/en_us/sitio_personas/lanpass/como_acumular/volando/volando_en_ow_asociadas.html?rand=0.226548513568396