Expectations are a big thing as well. We are fortunate enough to have the ability to pay for child care for our kids. As a result, my wife and I have been able to continue on with our careers and both admit that we are better parents because we are able to go to work, be ourselves, act like adults, and spend time with our kids, mornings, evenings and weekends. Most people might feel guilty about not wanting to be a stay at home parent, but we aren't, I think it would be very very difficult.
You also need to make time for yourself. First, you should make sure you have couple time and second "bro/girl" time. If you don't and you do nothing for yourself, you will come to resent all of it.
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