I did this with my son- he wouldn’t nurse, and I pumped every three hours to establish my supply. It was really hard. I had a baby nurse for 4 weeks but no help after that, and my days were literally feeding, changing, pumping while playing on the baby mat, then holding my newborn to sleep. It was a sweet and exhausting time. I’m pregnant with number 2 and don’t think I could exclusively pump again while also parenting an older toddler.