I just checked the router and right now he is connected with the correct ip adress. But yesterday his computer did not show in the router, but he was still playing GT 5 and was chatting with his friends on Discord. I saw that he was connected through cable since the icon in the activity bar was correct.
I'm guessing he's bypassing the parental lock like this:
https://youtu.be/2sFD9TGYaRANot sure tho, don't think he managed to figure it out by himself, so I'm not entirely sure on how he did it.
But the thing that he can makes the parental controls a joke.
He's on GTA 5 with friends now and according to the router the internet should be blocked.
The firmware right now is 3.0.0.4.384_81695, going to update as soon as my home server is done with it's backup