If you are a single bitcoin investor, would you rather teach a trusted family member about Bitcoin than involve your personal lawyer. I ask this because I grew to understand that lawyers are good at handling confidential issues like Wills.
The duty of Lawyer is to ensure wills are followed strictly, but leaving your bitcoin totally in the hands of a lawyer is entrusting it to a third party totally which is wrong, additionally leaving it in the hands of only a family member poses the risk of him taking all your funds when you are gone.
A good option might be creating a multi-sig wallet, let the family member be part of it as well as your lawyer, that way the family member cannot take it all for themselves and the lawyer must ensure your will and distribution formula is strictly followed before he authorizes transaction.
You're right the right thing to do is to save it in a multi _sig wallet so both your family and layer will be aware of it so that at the event of your passing away no body can take what you have suffered to earn and save through your hard work because the fact is that there are situations that even layers has diverted the properties of their clients when the family is not aware of such properties, what I will say is that in any thing that we are doing whether is Bitcoin not don't just let only one person know what you have atleast tell it to two to three different persons in that way the security of such a thing will be more