Network problems!

I have a wireless network. my base station router is a Linksys WMP54G and I have a Linksys WMP54GS network adapter card in my sons PC which has Simply Mepis 6.0 on one hard drive and Xandros 3.0 on another which I can set either one to use at my choice to boot into. I have 3 hard drives in my basestation which i have XP Home on one hard drive and SimplyMepis 6.0 on another and Xandros 3.0 on another hard drive.  When I'm in any of the 2 LINUX OS's at my basestation,(SimplyMepis or Xandros) I can't find my sons PC, which is presently booted into the SimplyMepis 6.0 hard drive in his PC. All I really want him to be able to do is to get his PC online wirelessly thru my basestation, which is wired to the router, and the cable modem. Doesn't Linksys have any drivers for any Linux OS's that will be able to work with a Linksys WRT54GS card that is in his PC? Neither one of those OS's in his PC will find the basestation to get online.
Any help will be great!
Thank you, Jim

[Moderator]

I guess I'm missing something. Ideally both machines should wirelessly connect to the router which directly connects to the broadband modem.

You don't need to go through another computer. You just need a wireless adapter that is usable by the OS.

Would I be right in thinking you don't have a wireless router?  Just two computers with wireless network cards, plus a wired router and modem?  Are you trying to use your PC as a wireless router?

I have no experience of setting up a Linux box as a wireless router.  I prefer to leave gateway tasks to dedicated boxes designed for the job.