MAKING ONE OF YOUR CHILDREN CO-OWNER OF YOUR BANK ACCOUNT IS DANGEROUS

I have written about it before, but it obviously can't be repeated too often because it keeps coming up: it just is not a good idea to make one of your children a co-owner of your bank account, for at least three reasons: (1) a co-owner can remove the contents of the account without your approval; (2) a co-owner's creditors can collect the co-owner's debts from your account; and (3) after you have passed away, the co-owner doesn't have to share the account with your other children, even if the co-owner promised to do so.
I have seen that third scenario more times than I can count.  Needless to say, it destroys family harmony.  Isn't the cost of a will worth avoiding that outcome?