We need more information.
Is the printer directly connected to your parent's machine, or connected to their network (e.g., connected to their router)?
Assuming the printer is accessible from the network: Have you installed the printer's driver Mac OSX software package on your MacBook (btw, MBPro?)?
If not, you need to go to the printer maker's website and download/install that model's Mac software package on your laptop. For example, my HP 8600 printer was installed on my PC with their Windows drivers, and I needed to install the HP 8600 Mac software on my MBP before I could print to the 8600 over our home network.
Usually, during the set-up process the installation software attempts to find the printer to verify that it will be ready for use on your laptop. If you have already installed the printer's Mac software, what happened during the installation process?
More help when we have more information