In the grand scheme of life, if you have 2-3 kids on a typical age distribution, the years in which at least one needs to be taken care of the majority of the time is 10-15 years. You'll likely have 2-4x as much time where you're both lucid and not responsible for childcare.

Incidentally, that ~decade will likely be the most precious of your life; don't miss it. [1]

1. https://avc.com/2010/06/being-present/