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How do you balance privacy with ensuring your heirs even know the Bitcoin exists?
As your heirs come of age, teach them about encrypted messaging. Furthermore, consider running your own messaging server and setting up a time-locked, encrypted message perhaps scheduled for 10 years into the future (which can be readjusted), stating something like: "I have set aside some Bitcoin for you at this address: xxxx, and you can access it only by following these steps: ..."
In the meantime, create a set of clues linked to that time-locked message that will lead them to the privkeys, designed in such a way that only your heirs would be able to decipher them.
Inspired by "Transformers: The Last Knight"; with an approach like this, your life becomes just like an action movie, lol!