My family knows where to find my recovery phrases and other pieces of information to recover all my coins, but they don't have a copy of anything in their hands. There is no reason for them to have copies of the seeds for cold storage. They know what they have to do and where to look for the essentials for recovery if one day I don't come back home. That's it. My family isn't interested in Bitcoin, only I am. I am sure they will gladly convert in into fiat one day when I am gone.
Thank Y'all for sharing your different ways and opinion. Truly we have different family background and different culture that's why we have couldn't agree some of other's opinion. But As a young man and unmarried person, I think this reply is the best way that I can follow as I have no sons or daughters yet lol.
I will only share copies of my keys to my children someday and it's up to them how they will handle their money.