Gliding is a cheaper way to start
Perhaps the OP should look into gliding...
Under EASA rules he can solo at 14 and get a gliding license at 16. Many clubs have significant discounts for young members.
If he spends his 16th year as a genuine PIC, power add-on should be "relatively" simple, and he'll have the confidence with the examiner that only real PIC time can bring.
In my experience, big things in life should be broken down into achievable bits. If there are rewards along the way (like solo at 14 instead of waiting until 16) or taking Mum or Dad for a ride at 16 instead of 17, then so much the better. In the US Army there is a term "Plan of Action and Milestones." This addresses the question "where do you want to go, and how do you know you are progressing in the right way?"
Yes, I'm biased (SEP/MEP/IR PPL but instructor only for gliders), but I think the earlier he can achieve valuable milestones the better.
Terry