Every once in a while a high-profile woman will divulge the dirty underbelly of trying to be a woman in the work world. I remember the first time I saw it. It was when Brenda Barnes stepped down from a huge career at Pepsi to be with her kids. And she announced that she felt like a bad parent spending so much time away from them. Thereby implying that the other moms with huge jobs like hers were also ignoring their kids.

This week, there is another ground-breaking example of a woman stepping down from a very high place: Anne-Marie Slaughter (pictured above). She is a dean at Princeton and she was director of policy planning in the State Department. She wrote a breathtaking article in the Atlantic titled, Why Women Still Can’t Have it All, about stepping down from her State Department job to take care of her two teenaged boys. She says, in the article, that she is taking much better care of them when she is not away from them.

This shouldn’t be groundbreaking to say. But after twenty years of deafening feminist diatribe it is actually controversial to say that a mom is a better mom if she is home with her kids. So that in itself makes the Atlantic article worth reading.

Here’s another thing Slaughter does that I love. She takes down Sheryl Sandberg for telling other women to be like her and spend their days working insane hours for startups. I have written before about how ludicrous is is for Sandberg to think she’s a role model for women when there is a huge amount of research to say that women who have kids want part-time jobs. Sandberg assumes that women want high-powered jobs like hers and don’t have those jobs because there are no role models. Slaughter sets the record straight: women don’t want high powered jobs because they want to be home with their kids.

It’s ridiculous that it’s controversial to say that most women want to parent differently than most men. It’s ridiculous because there is scientific basis for this and a social basis for this and the women who argue against it are always women who do not have school-aged kids and a high powered job. So you know what? If you are going to argue in the comments section that women can have a high-powered job and school aged kids, please qualify yourself with the age of your kids and the number of hours you work per week.

Here’s how many hours I worked at my startup when I had young kids: 80. And my investors thought I was part-time—which I was, compared to how many hours other startup founders work. I’m just putting a number out there so you can have a benchmark for what high-pressure, high-powered jobs demand. Slaughter traveled almost nonstop for her job. And so do most people at that level.

So I loved Slaughter’s article. And I loved that women are coming forward to say that it is literally impossible to have a high-powered career while you have young kids, if you want to be involved in your kids’ lives. The best thing older women can do for younger women right now is to tell the truth. It’s hard to tell the truth because if you are trying to do the high-powered job and the kids, you will kill your career by admitting that it’s impossible.

But here’s the truth for women: You should not plan your life so that you work until you’re 30 and then have kids, and also have a huge career. Because you will be taking care of kids during the very time when all the men you worked with are working harder and longer hours than ever before. Men who have kids are in a great position to climb the ladder. They have wives at home. Women cannot go full speed ahead until the kids are grown up. Slaughter has great evidence for this. But you should be able just to look around and see that this truth. My favorite example: All the male Supreme Court Justices have families. Two of the three women do not. And the one who does, Ruth Bader Ginsburg, did not start her career until her kids were grown.

Slaughter lays out a great plan. It’s tucked into the article, among a lot of other calls to action. But she says, if you want to have a huge career, have kids when you are 25 so your kids will be grown when you are 45, because there will still be time to have a huge career.

Of all the ideas for having a big career and being a mom, this is the best one out there. Young women should use what we’ve learned so far and do things better than the generations that have come earlier. It’s too late for Generation Y since most of them have past the age when they would need to be finding a guy to marry. But there’s hope for the women of Generation Z.

Women from age 20 to 25 should focus on finding a guy to marry, and then build your career slowly, while you have kids. Which is what other generations did—they just started having kids five or ten years later.

This also means women will need to start dating men who are older than they are. This also seems like a good idea. Men, of course, love younger women. But more than that, women who are in their twenties are in their prime in terms of self-confidence. They are physically very desirable, and they are doing better at work than men. Men, on the other hand, are at their nadir of self-confidence in their twenties. They are not making money, which is something that is very valuable on the dating scene. And they are not doing as well as women at work. Men look way better in their 30s when the women have left the workplace and the men have a more solid grip on their earning power.

So men and women dating in their 20s is a lot like girls and boys slow dancing when their are 12. The girls are so much farther along developmentally that it’s absurd.

So look. Here’s my first post directed solely at Generation Z women: Spend the years from age 20-25 focused on getting married. There is no evidence that doing well in school during that period of your life will get you worthwhile benefits. There is no evidence that waiting longer than 25 makes a better marriage. And there is not evidence that women who do a great job early in their career can bank on that later in their career. There is evidence, though, that women who focus on marriage have better marriages. There is evidence that women who have kids earlier have healthier kids, and there is evidence, now, that women who have grown children by age 45 do better at getting to the top in the workforce than all other women with kids.