|It is possible using Internet Connection Sharing. But why? Sharing the Internet through a wireless connection is going to be problematic as the best of times.|
As you have a wireless router it would be far more reliable and a lot simpler to connect the desktop directly to the router the same as the laptop even if it means installing a wireless network card in the desktop. Most if not all wireless routers have a built-in switch with four Ethernet ports which can be used to connect directly by cable. This would be the best solution.
What is the model number of this router?