That is why it is important that our family know that we are investing in bitcoins. Teach them how to use and store bitcoins. Tell them where you store your bitcoins and write your passwords and store them in a safety deposit box which they can access in case something happens to you.
But I have few satoshi so telling password of my wallet will not change my family members life even they will not try to check. So just think if so many people lose Bitcoin(satoshi) like me than how many Bitcoins are lost every year?