I work, and then whenever I have any other time, I'm with my daughter, and then I go to sleep. I think you basically have to abandon the dreams of having any other adult activities in your life. You have to go to sleep whenever your child goes to sleep. That's basically how we're doing it.
And I'm a slow writer: five, six hundred words is a good day. That's the reason it took me 20 years to write those million and a half words of the Civil War.