text: If your brother spends a lot of time on the internet, using the computer for his needs, and not letting anyone else on it.  Then say to your mom, that buying a laptop, even a cheap one, and a router, that will allow him to be on the laptop doing his thing and someone else on the main computer.  Also, with a router, you are able to limit the time he spends on the internet, what time he can get on the internet, and even what sites he gets on, all of which can be blocks be a password for only the parents knowing.  Wireless home networks can be great safety tools if they are used right.