If you have more than one child, do you have a favorite?

A new book suggests that any parent who says “no” is kidding themselves. “I like to say that 99 percent of all parents do have a favorite child and the other 1 percent are lying through their teeth,” says Jeffrey Kluger, author of “The Sibling Effect:What the Bonds Among Brothers and Sisters Reveal About Us,” (Riverhead Books, September 2011).

(Courtesy of Riverhead Books)

He cites a study by a University of California, Davis sibling expert that videotaped and followed families over time. It concluded parents often treat their children in ways that reveal bias and that the children know exactly what’s going on.

Parents may side consistently in an argument or cheer more readily for one child. They may come down harder on the other child or children. The actions and reactions may be subtle. But they exist, according to the study and several experts that Kluger quotes.

Kluger attributes favoritism to a number of possible factors — genes, compassion, sibling order, personality, gender. As for the effect, predictably favoritism can trigger resentment, competitiveness between siblings (he uses the Kennedy clan as an example) and lingering self-esteem problems.

There’s also evidence that the most favored child will have problems. Being a golden child may yield severe disappointment as the child gets older and fails to exceed expectations outside the home.

As a parent of two, I will tell anyone that I favor my daughters equally. No, really. That said, in any given moment, I might feel more warmly toward one or the other (at 3 a.m., the better sleeper is my favorite; at 6 p.m., it’s the one who eats without complaint). Is that favoritism? Not necessarily the kind Kluger is talking about, but I admit I may be in denial about my true feelings here.

My own parents might also attest that they had no favorites among their five girls, despite the fact that my father carried a picture of just one of us in his wallet when he went off to work each day. (Dad, if you’re reading this: No grudge. I swear.)

Kluger pays little attention to parental protests to the contrary and instead cites psychologists who say parents should focus on minimizing the manifestation of any favoritism. A good way to do this is by acknowledging each child’s individuality. Art classes for one and soccer for another, and different academic goals based on varying abilities. Treating children differently is normal, the experts say, as long as the treatment is fair.

As for eradicating favoritism altogether, Kluger says it’s a futile exercise.

Do all families with siblings have a favorite child? Do you have a favorite and, if so, how do you deal with it?