What you call profile, is called "user account" in Mac OS X and other OSs.
If you open System Preferences > Network, you will see a drop down menu at the top with the word "
Location" on the left side of it. That is where pre-configured network settings can be chosen. Check if all three user accounts have the same location chosen, it most probably is set to "
Automatic" on "Mom" and "Dad".
If you connect via Ethernet cable, go to System Preferences > Network > Ethernet > Advanced (button in the bottom right) > and click on every tab there is and write down the settings. You can also do screenshots and copy them later to a flash drive or the Shared user account (Macintosh HD / Users / Shared), you just need them (notes or screenshots) to compare. Do that with every user account.
If you connect via wireless LAN (AirPort), go to System Preferences > Network > AirPort > Advanced (button in the bottom right) > and click on every tab there is and write down the settings.
You can also do screenshots and copy them later to a flash drive or the Shared user account (Macintosh HD / Users / Shared), you just need them (notes or screenshots) to compare. Do that with every user account.
Now that you have taken notes or screenshots in every account, see what does not match with the two working user accounts and change that accordingly in the "Son" account.
Was that understandable?
Taking screenshots in Mac OS X.
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