Else, have some faith on your wife and tell her everything about your bitcoins. Let her know how to access it and ask her to distribute it among your children after your death. But if you are holding a very small amount, then it's not worth having the bitcoin details included in your will.
I think no need to make a will of testament just to remind them about your Bitcoin or Cryptocurrency wealth. Your wife or your closest sibling will be the best person to entrust all your digital wealth because nobody knows what will happen. If we die they can still use our digital wealth.
That's the best thing, introduce Bitcoin and Crypto-Currency and Blockchain technology to your family in order to remind them that if one of the family member is gone then they can still access your assets.