"I went back and forth and then finally I decided that I couldn't do the level, I couldn't be at the level I needed to be at the job I was doing and also do what I wanted to do with Jackson," Knox told CBS News correspondent Kelly Wallace.
Knox, who's 33, was student body president at Northwestern Law School. She never expected to be an example of a heated debate these days: mothers opting out of work.
"I never planned to stay at home," she said. "I'm really not a homemaker. I wasn't at the time. I'm much better now."
Ever since the New York Times profiled some highly educated career women who gave it up to become full-time moms, "opting out" has been seen as the latest trend in mothering – a kind of social revolution.
But the question is why did these women turn their backs on corporate America to be home with their kids? Did they opt out or did they run out of options?
"It's a myth," said Sociologist Pam Stone, author of Optiong Out: Why Women Really Quit and Head Home. "It's a myth in two ways. There's no revolution and women aren't opting out, they are being shut out."
In researching her new book, Stone found most left top careers with great reluctance.
"I really expected that I was going to hear them telling me all about family and all about the pulls of family," Stone said. "But instead what I found is they were talking a lot about work, and it was the conditions of their jobs that were really forcing them out, forcing them into making a decision."
Philosopher Linda Hirshman has a different take. She believes women are choosing to walk away from work — and making a big mistake.
Her book — Get To Work — outraged many stay-at-home.
"If you opt out, you do not use your full talents and abilities, for the most part," Hirshman said. "If you try to get back, it's very hard to get back to the place that you left."
Hirshman wonders why it's always the women struggling to balance work and family.
"If working part-time is such a great idea, why aren't men doing it?" Hirshman said. "They are not doing it."
Some women say it's not opting out, it's opting different.
"It's not fair to say you're opting out and that's it, you're no longer working or wanting to work, it's where you're opting out of a certain level of work or job or certain lifestyle," she said.
That's what Nicole Knox has done. She started a law firm from home.
Business — and her family, she says — are thriving.