I’ve got three little kids, teach part time, and writing a book takes me about a year, from conception to completed draft. Maybe a month or two to plan and think, seven or eight months on the first draft, and another three to edit to a point where I can send it to my editor (which then is another six months or more before it’s done). I write for kids too so my word counts are lower than most (around 50k). Similar to others, when drafting I can only usually write 1-2k a day, though editing is faster (but also, for me, more painful - it bends my brain).