Dad of two here. Good question. What I'm reading in your question that many replies are missing out on is that your question is less about the actual responsib

Dad of two here. Good question. What I'm reading in your question that many replies are missing out on is that your question is less about the actual responsibilities, which I see you happy to take up. It is about what to do with your mind which, now when not at work, can only think about your kids. Also there is this feeling that you should put your kids first and above yourself. If that is the case, focusing inward helps. If you're at a place or time where your kids are not a matter - they might be safe and sound asleep, you may be on a work trip, you may be up a bit early on a day, whatever; at that time, you can tell yourself that it is OK to focus on your expansion. I also found the time constraint changing what leveling up means to me - instead of picking up that new framework or tool, going deeper into whatever I want to.