A good idea would be to implement some kind of mechanism that would automatically transfer all the coins to a specified account after a time threshold.
Example:
Person dies... This person configured a mechanism which will be triggered after 1 year.
1 year passed.
All coins are automatically transferred to configured account.
While the person is alive, the person is responsible to update the timer in some way to prove person is still alive. It will not be updated in case that person dies, and as result the function is executed.
That could be implemented in the Bitcoin protocol itself. Not sure if this would be possible, but maybe there are other ways.
it is possible and it is called locktime, you create a transaction and set the locktime of the transaction to a specific time or block height that you like and then sign it. you can give it to anyone, put it up in a server that broadcasts it at a specific time or just post it in public, that transaction can not be mined until the locktime is reached.
and if you were alive by the deadline you should spend the funds to a new address before the tx becomes valid.