Death and cancer. This is a profound question and very important. It depends on the age of the children and the situation concerning the cancer. Is the other parent there to help? I would discuss this with your doctor, and hopefully you are in a support group that can help you. Also if you have religeous faith you can discuss it with chuch members. Hopefully you wil get well and not have to face this problem.
Very carefully.. The best way to accomplish this(if there is a best way) is to be honest and as reassuring as possible and try to make the child a part of the process that you are going through; to elevate his understanding. I do not know the age of your child as that would certainly play a part in the discussion...And you may meed to involve a child 'therapist' to assist you in preparing. Blessings to you!
IOH. Please contact members of Inheritiance of Hope.org-this is a very charitable organization, which exclusively deals with this issue. Contact these wonderful people who run reteats for familiies and counseling- ask for my daughter, Lara Miller.