My internet connection keeps disconnecting and I don't know why..Can someone please help me?

Well here is the situation. I have Netgear wireless internet and my brother's xbox is connected to the internet and my laptop is connected to the internet at the same time my sister is on the home computer. And it is working for like I would say about 5 hours and then out of nowhere it gets disconnected. My internet connection is excellent so I don't know why it would disconnect. Can someone plz help??