Using my own experience as a guide, I think many young people may underestimate the impact of having a family on their career. Given the amount of books, articles, and blogs I see about "work/life" balance, the same issue appears over and over again. How can I maintain a good career and enjoy a healthy family life? Here's my answer: get the best, most valuable skills you can in whatever career you choose, so that you can move jobs or become self-employed and make your own rules. Otherwise you will be forced onto someone else's treadmill.
I graduated from high school in 1989. Feminism of the 1970s and 1980s was supposed to have stamped out sexism and opened up job opportunities for women; in many respects it did. I can't recall ever thinking that there was any job/career not open to me. This was a gift - and I thank my parents and the women's movement for it. Having it all (great work, great family) seemed truly possible. And thankfully, the desire to spend time with family while having a good career has expanded to include more men. On average, fathers now spend more time with their children than their own fathers did. Good news for everyone.
But the reality is that the workplace, and particularly now in the U.S. with such long work hours expected in most jobs, is not family friendly. This isn't necessarily sexist, although it disproportionately impacts women since women continue to do the bulk of domestic work. But it impacts parents. Good childcare is hard to find and expensive, and some parents do not want to outsource 100% of their childcare. Flexible schedules are hard to negotiate and find.
To find part-time work, flexible schedules, or a work day that allows you to get home by 6:30 p.m. most nights, you must find the right employer. And some careers lend themselves to better work hours than others. So when you're looking at a career, work schedule and availability of contract work or self-employment may be important. See informational interviewing. I know researching that issue was important for me when I chose law. I knew I could "hang a shingle" and become self-employed if I needed to - and sure enough, I needed to and it worked out well.