this is not their fault. There is nothing they, or anyone, could have done to change what is happening.
medical professionals have done all they can and now there are no more medicines to prolong life.
there is no right or wrong way to respond to what they have heard. Encourage them to express their feelings honestly and openly.
they cannot catch the illness. It is OK to cuddle or touch.
any changes to routine, for example who takes them to sports practice or school.
they will be looked after. If you (or your partner) are terminally ill, you may be arranging for someone else to care for the children after your death. Let children know what your plans are and how this will be managed.
they can talk to you and ask questions any time. Reassure them that you are OK with this and these conversations will not upset you.