Life After 'Sex'

She may be famous for her style, but there’s at least one person who would rather see Sarah Jessica Parker in sweatpants than Oscar de la Renta: her 4-year-old son, James Wilkie. “He saw me dressed the other night and said, ‘I want you to go right back upstairs and take that dress off!'” she recalls, laughing. “His strongest feelings about my clothing are that I take it off, because that means I’m staying home.” And for the most part, she has been—although this month marks a (small) return to the spotlight with her new clothing line, Bitten, for Steve & Barry’s, which hits the budget fashion chain’s stores June 7. Still, James Wilkie, her son with Matthew Broderick, needn’t worry: As Parker, 42, recently revealed to PEOPLE’s Charlotte Triggs, her main focus these days remains teaching him the facts of life.

He doesn’t like you to dress up, but how do you like James Wilkie to dress?

I let him make those decisions for himself, but I did make him wear what he calls “fancy shoes”—which is just a simple, white leather boy’s shoe—at my brother’s wedding. He really wanted to wear his Crocs. He was upset about it, but I promised he could put on his Crocs the second we got home. He reconciled to that.

You’ve been offered design jobs before. Why take this one, for a budget chain?

It always seemed very unsavory to ponder a real design job. I don’t sketch. I don’t know how to sew. But I am acutely aware of what it means to not have the things you need, let alone the things you want. And you should be able to have affordable, quality fashion.

Every piece from your line is less than $20—but if a woman’s going to splurge on one item, what should it be?

I tend to be someone who splurges on shoes. I know a lot of people splurge on decorative jackets, but I don’t because I don’t look good in them. I’ve got too much hair, and I don’t know how to pull it up myself to get it out of the way of the jacket!

What did you learn, style-wise, from being on Sex and the City?

That there shouldn’t be rules! I always believed in hard-core aesthetic rules—”No white after Labor Day.” And I matched, because I thought that was ladylike. I matched my clothes my whole life—at least until [costume designer] Pat Field got ahold of me!

You must have an amazing closet.

I have five sisters and three sisters-in-law, and they’re all on the receiving end of lots of stuff! But I would say 70 percent of what Carrie [Bradshaw, her Sex and the City alter ego] wore, I still have. And I have every dress I’ve ever worn to an important event that wasn’t borrowed. I have some Calvin Klein pieces from the early ’90s that say ‘Kate Moss‘ in the back, because they were from the runway show. So that’s nice.

James Wilkie is 4 now. Has he begun asking tough questions?

He goes to school with a lot of kids who have different families from his, so he’ll be like, “Jen has two mommas” or “Charlie has two poppas.” And so we’ve been talking about what it is to be gay; I want him to understand it in terms that aren’t overwhelming to him. But he asks about everything. Death is a very big conversation piece.

Do you have trouble explaining these things to him?

Actually, the things that are far more complicated for me to answer are any kind of science questions. He has a really keen interest in science. I have basic fundamental knowledge—but I don’t know what he’s going to do about homework! I’m glad my husband’s smart about that sort of thing.

Your 10th wedding anniversary was May 19. How did you celebrate?

In a private way! He did write me a card, and I didn’t have to ask, which was really nice. He’s been shooting a movie, so he’s not been around much, but we had a great, great anniversary.

In Hollywood 10 years is a big deal, so congratulations.

I know! And it’s 15 total [since we met]. I’m really shocked! Not because I’m shocked that we lasted—it’s just a lot of years. You can’t stop time!