I had the opposite to the commenters above. I had the best ideas when attending to the baby, middle of the nights. I also started reading serious books (like geopolitical stuff) when my baby was falling asleep on my laps. I did some of my best and most efficient coding the first 3 months with the baby (when it was sleeping). I worked less, but better. My brain definitely shifted, I had an unparalleled motivation to do things. After 10 months it started to fade away and return to “normal”.