I went to market with my wife to buy things for our new born baby, after my wife selected baby things that Worth thousands and I paid with my btc,the transaction was very easy and faster. When we returned home ,she asked if you die can I achieved your btc or continued with your account? Because it's very easy and faster in trading and transaction.
Yes she could if you would tell her all of the important details like password and emails and which site you use for trades.
I have it all written down so if anything happens they would know how to convert it into cash.
But for me it is better to teach them now so both of you would have more things to talk to and common interests.