Forget The Brady Bunch. The only place that stepmoms and dads and kids sit around the fireplace popping corn and grinning from ear to ear is on TV. Reality, for many stepfamilies, is an uncomfortable diet of frayed nerves and gnawing anxiety. Yet with as many as 500,000 women joining the ranks of America's estimated 25 million stepmothers each year, the search for better understanding goes on. To write Stepmotherhood: How to Survive Without Feeling Frustrated, Left Out, or Wicked (Times Books, $14.95), freelance journalist Cherie Burns, stepmother for eight years to Anne Duncan Cooley, 24, and Hope Duncan, 21, interviewed more than 40 women who had taken on part of the job of raising other mothers' children. Speaking to reporter Gay Daly while her own kids, Alex, 4, and Jessie, 2, played in another room, Burns began with a caution: "I don't set myself up as a model. I still have the same problems as other stepmothers."

What mistakes do stepmothers tend to make at the start?

I found that most women had not talked enough with their husbands. The nitty gritty: Are we going to take vacations with the kids? How much child support do you pay each month? These are the things that begin to chafe if they don't go right. The other mistake women make is to have unrealistically high expectations. You assume that you'll be just one big, happy family sitting around the table eating turkey together.

Where do those expectations come from?

There are no models for stepmothers yet, except negative ones. You turn to the only other model you have—mothers, and you try to make that work. It doesn't. I immediately invested some of myself in my stepdaughters—trying to make them more like me. If they weren't dressed well enough, I thought, "Somehow I should help remedy that." If they didn't write thank-you notes, I thought, "I should be part of correcting that." After all, what do mothers do? They teach you. But stepchildren don't welcome that kind of interference. It might be more caring to stand back.

What do kids do to let the stepmother know that they're not comfortable?

They mention their mother a lot. They make comparisons. I talked to assertive, disciplined women who sat there in tears telling me about a child who said, "Her spaghetti sauce is better." These things sound so petty, but they are the things that get to people. Kids also talk a lot about the past, saying, "Oh Dad, remember when I locked Sis out and you and Mom were sleeping late?" They have their ways of ignoring you. Not looking you in the eye is the one I heard about the most. It's their way of saying, "I'm not ready to accept you."

What if, in spite of your best efforts, you don't like your stepchildren?

That's when you really have to look inside yourself. Are you jealous of them? Is it jealousy of an ex-wife? Do you feel they're siphoning off money from your needs and wants? Before you talk about these problems with your husband or the kids, it might really help to have a counselor or therapist to whom you can say freely, "This is why I don't like these kids." The most difficult situation is when they're just not your kind of people. It may help to know a lot of women feel that way. But you are going to have to live with these children.

Is the guilt that stepmothers may feel sometimes misplaced?

Sure. Too many stepmothers whom I interviewed were treated poorly by stepkids and then felt guilty because they didn't like them. They wouldn't have felt that way about a thoughtless niece or nephew.

How do you handle discipline? Do you leave it to the father, or is that the coward's way out?

Professionals in the field say you can't be effective as an authority until you have some kind of trust. So they suggest that you lie low for a good while. That doesn't mean you have to let people walk all over you, but don't rush in and give orders. The father has to help ease you into things.

How long does it take to establish trust?

It depends. After you get acquainted you can certainly ask kids to help around the house, but it takes about three years for the relationship to settle out. I can just hear the audible gasps as I say that, because no stepmother wants to think, "We're going to be hashing things through here for three years?" But that can also be encouraging. If things go badly at first, you can remind yourself that there's still time.

How about husbands? What sort of mistakes do they make?

Husbands tend to assume that everything will fall into place. You hear of divorced dads who were happy to have the kids eat take-out Chinese food when they were bachelors, but after they remarry suddenly that isn't good enough. They want a home to share with the kids. It's a perfectly natural reaction, but it puts a burden of anxiety on the stepmother who may be unfamiliar with the new role or unhappy with the labors involved.

What if the father spoils his children and you feel uncomfortable about it?

It's touchy. If this happens early in the marriage, you probably ought not to say much. It may be part of the settling-in phase during which the father is trying to show the kids that he still loves them. If it continues, you'll have to bring it up, but plot your course carefully. Those discussions can turn into damaging arguments.

Why? What goes wrong?

A lot of times the stepmother holds it in for months. Then the first time she sits her husband down to talk, he says, "Susan, I think you're being ridiculous about this," and she blows up and says something like, "You know, I don't really like those kids, and you're being ridiculous the way you treat them, and what about my birthday that we spent at the zoo?" It doesn't help to explode and get it off your chest if what you're after is getting your husband to change his behavior. He's just going to say to himself, "Very overwrought woman."

What should you do instead?

You have to try to get him to talk, which is hard, because a lot of fathers don't want to talk about these things. Once you hit a nerve, men tend to close up completely. If your relationship is good, he may open up and you'll get somewhere. At this point you have to show some evidence of having the best interest of the child at heart. He needs to see that you can be kind, too.

What builds the relationship between stepmother and stepchild?

Vacations can be difficult, but they seem to be the situations in which a lot happens. The stepmother may decide the child is not so bad or vice versa. She may have to be a good sport and put on the waders, sit through the rock concert—whatever. That's how you build a history together.

How can money become a problem for stepmothers?

What you hear about from so many stepmothers are financially strapped second families and divorce agreements that the stepmothers think are unrealistic. But here, too, the shocking thing is that people don't talk about it beforehand. Women go into marriage as though everything a husband makes is going to be theirs. Then when they see that it's not, they take it as something stolen from them. And that really isn't fair.

What happens when anew baby is born into a second family?

The stepchild worries that he's no longer No. 1. The father can do a lot in this situation. It really helps to say, especially to young children, "Hey, this reminds me of when you were born." Children love their own histories. That may annoy the stepmother a bit because she wants to turn all the focus on her baby, but a grown-up can handle that.

Can a new baby strengthen the family?

Definitely. I saw that when my own kids were born. It helps the stepmother relax a little; it gives her a sense of belonging. And the lines of division begin to fall away. The stepchild no longer feels as if he's an intruder on a couple's relationship. You see fathers who go back and lavish a lot of attention on older children. The new baby renews their vigor for fathering.

Is it likely that you and your stepchildren will grow to love each other?

It may happen, but often that expectation causes a problem, because then anything short of love feels like a failure. The relationship between stepmother and stepchild is really very much like an arranged marriage; it's set up because there are a lot of good reasons for this couple to be together in a mutually cooperative relationship. And if you arrive at love, that's a nice surprise.

What are the rewards of being a stepmother?

When I look at what I have with my stepdaughters, I see that it's not a mother-daughter relationship, and we're not sisters either. But we meet on common ground. We've shared troubles, good times, even loved ones. That means a lot. When you do get a sign of affection from a stepchild, it's just great because you know they didn't have to do it. When one of my stepdaughters got married recently, she didn't have to make sure that there was a corsage waiting for me too—but she did.