Wireless network works but no internet

Hello,

alright, so i have a wireless network setup with my computer and my mothers

the setup goes phone jack => modem => wireless router => my computer(wired) + mothers comp (wireless)


NOW, my computer connected thru ethernet thru the wireless router connects to the internet just fine. My mothers computer is setup and is connected to the wireless network but yet doesnt have internet access.

So both connected to network. I have int access, she does not.

Ive restarted everything at least once, and this lack of internet on mothers computer thru wireless network also happened on our last network, and on the last network with the last computer

so we had this problem, replaced the computer, still had it and replaced the network, still have it

She is connected to network but cannot connect to internet through it