That's mine; I don't know the kids'. They took their keyboards to bed with them and wrote as long as I'd let them.
Here are some words that are music to a mother's ear: "I am having so much fun writing this! My book is getting exciting and I can't stop writing!"
That was my nonwriting boy talking. Now I doubt I will like his novel; it's a science fiction story set sometime in the future. There are weapons and weird things like body-function monitors embedded in the spinal cord. Or something like that.
The point is, he's enjoying the process of writing. So that helps me to carry on.