If the drivers for the printer aren't installed on your brother's computer, then the printer will not work. Everything attached to a computer needs a driver, including the internals, like the graphics card (through the desktop) and the RAM (through the BIOS). When you reconnect it to your computer, it will work because I am assuming that you have the latest drivers installed. However, if you try to plug in the printer to your computer without the proper drivers, then it will NOT work.
I hope this helps!
