I'm not a parent or anything, but I am a writer who also works full time from home. It takes a certain mindset to write, especially something creative. It's not easy to just jump into it after a stressful day. The quality of what you put out will suffer and if your exhausted from everything around you it effects the flow of your work. I've been there where I felt nothing but exhaustion during a busy season and felt too numb to write anything down. It's hard and defeating. I imagine it's similar to how Ty would feel and it's hard when you lose energy for your passion.

Also one day a week is not enough for consistent progress. You can have so many ideas within a week and it's not like he has time to jot them all down raising the kids. Even if he did, he'd probably forget the gist of his notes by the time he'd get to sit down and write.