ichat not video conferencing

My brother has bought a macbook today and we have tried to have a multi-person video chat but for some reason the green video box only show one way chat on my brother's name. I hope people can make some sense of what i'm tryin to say and can help with a reason why.

first of all, make sure that everybody who is trying to use the video has their isight set up correctly. not that hard if its built-in, just check the preferrences in ichat to ensure that its working. You might want to post a little more info, theres a number of things it could possibly be

try control-click and then i think there should be a button to add a person to the chat.