When I told my girls I have cancer, their reactions were age-appropriate.
Stella (5) wanted to pick me pea pods and flowers from the garden to make me better and came home for several days with "Do you still have two boobs?" as the first question out of her mouth. We don't talk about it a lot, but she asked to feel the lump near my armpit and knows what all the extra hand-washing is for. Several weeks later now I'd like to say she's a more patient kid, more prone to stripping wallpaper in her spare time or not whining in the morning, but alas... she's still five.
Frances (2) decided the cancer was all about her, so looks down her own shirt and pronounces, apropos of nothing, "Well, I have two boobies!" Maybe it's the proximity to her halcyon breastfeeding days, not that long ago, or the general understanding that Frances still = mommy so nothing bad could ever really happen to her, but she's generally not fussed about it. I like it that way.
What could be a challenge, but wasn't an issue with round one and my parents in town, is dealing with the side effects from chemo and the way my two lovely creatures will eventually lose their patience with mom the layabout. They say they'll be nice to mommy and all, but when I ring my little sick bell (oh, how I'd love to actually have a sick bell), who's to say they won't come with their list of demands rather than a cup of ice chips?
Remains to be seen, but man, when they're not being pains in the arse, they're kinda nice to have around. And ain't no way I'm not going to see how it all turns out.