My children have helped me inadvertently, of course, by simply being alive - I draw on their experiences and my own experiences in child-rearing when I write my stories. As the two oldest matured, however, they began to contribute more directly. I haven't forced my writing on them, but each of them has come to it in his or her own time, and once they are interested, they get the same "chapter privileges" that my wife has, if they want them - to get the chapters fresh from my having written them.
However, the most important connection, literarily speaking, is that they are both very talented writers. Without going into parental brag mode, let me simply say that Geoffrey's screenwriting has already won attention from producers, and Emily's poetry and short fiction have won awards and her first playscript was produced a few weeks ago. Neither of them writes at all like me, and neither of them writes the kind of thing I write. They have their own interests, and their own talents - in my judgment, at least, extraordinary ones. But they also have other interests as well, and they are certainly not following in Dad's footsteps. In short, you won't be seeing either one trying to sell sci-fi to Analog