I Need help with halo 3 multiplayer online?

[Patriot fan]

I already have an acount on xbox live but my sister wants to play online with me so if i create her an acount will i have to buy all the packs like the Lengendary pack from Halo 3.

 

[Jack]

no maps on hard drive not profile.

 

[halo pro]

no you will not have to because the maps are saved on the hard drive