You need a legacy project. Something that you can work towards as "your life's work" and leave it behind. The easiest route here is to have a child. If thats not a possibility you need something grander and philanthropic. Start a non profit org that helps people. Become a mentor and pass your knowledge on to some mentees.
Having a kid is certainly the default option, but far from the easiest, mostly because it is rather difficult to spread the burden among other people who believe in your 'legacy project' (but if you have an extended family that can pitch in or you can afford to add staff to your household, that becomes less of barrier).
