She went back to work after our youngest was old enough and busy enough with all her extracurricular activities and could get herself to them.
She works part-time and is always home when kids are (except summer) but probably does more in those 4-5 hours a day than I do in 8. (Shhh... don't tell her.)
Major transition for her after being a stay-at-home mom for almost 2 decades and I'm amazed by her.