Q: I’m about to marry a woman with two children, ages 6 and 8. I’ve heard that stepfamilies are more difficult to manage than first-time families. Is this true, and if so, what advice can you give to help us be a successful stepfamily?

A: About 7 percent of all children live with a biological parent and a stepparent. About eight of every 10 children living with a stepparent resides with their biological mother and a stepfather.

These statistics, however, only tell part of the story. When one takes into account both remarriages and cohabitation, nearly 30 percent of all children will spend at least a portion of their childhood in a stepfamily. Hence, stepfamilies, while not the rule, are more common than many people realize.

Unfortunately, research consistently finds that children reared in stepfamilies do not, on average, fare as well as children reared in households with continuously married parents. For example, children reared in stepfamilies are more likely to develop emotional and behavioral problems, fail at school and commit crimes, compared to those living in households with continuously married parents.

Indeed, even though remarriage brings more income and a second adult into the household, studies find remarriage by a single mother does not negate the adverse consequences associated with children who grow up in a single-parent family. On some measures, most especially crime, children in stepfamilies actually may do worse.

Making matters worse, second marriages run a greater risk of dissolution than first marriages, and the risk is even higher when children are involved. By some estimates, as many as two out of three stepfamilies break up.

These statistics can be viewed in several ways. The first is to interpret them to mean that all children in stepfamilies are doomed. This, of course, is untrue. Yes, being reared in a stepfamily raises the risk of poor outcomes for children. That doesn’t mean, however, that every child reared in a stepfamily experiences significant difficulties.

Moreover, simply emphasizing the negative doesn’t help stepfamilies be successful. It only serves to demoralize them.

The second way of looking at these statistics is to deny they exist. That’s like telling a smoker to ignore evidence that smoking increases the risk of developing lung cancer. But pretending a risk doesn’t exist doesn’t reduce that risk one bit. It only reduces one’s motivation to do something about it.

Fortunately, there is a third way to look at these statistics, and it is this: Precisely because children in stepfamilies are at greater risk of poor developmental outcomes than those in households with continuously married parents, we need to do a better job of giving stepfamilies the information and support they need to build and sustain healthy families.

If that sounds like commonsense, well, that’s because it is. Unfortunately, commonsense seems to be in awfully short supply these days.

So, here’s my advice for men who are about to become stepfathers, based on a review of the empirical literature on stepfamilies conducted by my research assistant Anna Degraffinreid:

Reaffirm your commitment to your wife daily. Use the knowledge that stepfamilies are hard on marriages as motivation to work to keep your marriage strong and vital. This means taking extra care to listen to your wife, compliment her, show appreciation for what she does and be affectionate toward her.

Eradicate unrealistic expectations. Recognize that stepfamilies are different from first-time families. Don’t expect that just because you and your wife walked down the aisle together means your children naturally will blend into one, big happy family. Instead, recognize that children in stepfamilies frequently experience loyalty conflicts between their new family and their older one. Becoming a successful stepfamily will take time. Be patient.