Whenever i see a dad trying to make his kids dreams come true, i feel the urge to help !
If i were you i would skip UE4 altogether and the cost of building a powerful rig. Forget about minimum requirements. After a while and as the project grows, even the best cpu starts to cry for mercy!
Instead i would buy a licence for Construct 2 (99$ i think) -after trying out the free version first- and spend 200-300$ for a really nice windows 10 tablet (10 inch +)with a keyboard. It is more than capable of running the software, you can hook it up to a tv or monitor and the most important of all he can take it with him and learn wherever he is.
It uses a visual scripting method that resembles Java and he can create awesome stuff with it. If after a year he still cares about creating games then go ahead and sell your car for his next desktop
Just my 2 cents.
Cheers.
He’s right ue4 is very complex I’m 15 and I find it hard in some vital areas