Perhaps our most authentic exchange occurred when, as an adult, I finally confronted him about his feelings toward me. He admitted that he thought that his new opportunities had been quashed by . Harsh? Sure. But honest, too. The fact is my father's ambivalence about me is not so uncommon.

Unconditional love is a wonderful ideal. That's why it is so disconcerting to learn that a parent's love has limitations. People are not designed to give endless and resources to a child—no matter how much they might want to—because the strategies that allowed our ancestors to pass on their genes sometimes involved setting limits on care and even choosing which of multiple children to invest most heavily in. My father made the ( ) decision to work hard for his entire family's future, but not to nurture or bond with a child who came knocking at an inconvenient moment in this endeavor.

Intergenerational conflict often springs from limited time and resources. Parents want to shelter and support their kids—but only to a point. Children want to experience that support for as long as possible. A significant number of parents may unwittingly give more attention to the first- and last-born, forcing middle children to work harder for attention and resources.

also plays a role in the war for parental attention. Boys tend to be favored under plentiful conditions because males with resources attract higher-quality mates. (Again, this psychological tendency operates below the level of conscious awareness.)

Finally, there's the clash of generations. Evolution proceeds through variation, and that includes cultural . Our parents' views, alas, are largely calcified by the time we hit puberty. If you're over 40, Facebook could look suspiciously like a portal to self-disclosure, and tattoos may be no more than "tramp stamps." But teens embrace that which differentiates them from their elders. When kids rebel, they react not to parental support but to their parents' values.

We're on the same team as our parents, but we don't play the same positions. We share 50 percent of our genes with each of our parents, but we differ in the other 50. This has emotional consequences. Ashley's mom eventually gets resentful if she has to drive to karate, ballet, piano lessons, and tutoring. Ashley, we love you, but this is ridiculous.

Why? Because parents are forced to make trade-offs they wouldn't make in an ideal world. Mom and Dad make an investment, the very definition of parental care, according to Robert Trivers, an evolutionary theorist. And return on investment is viewed from different perspectives by investor and investee because they have different .

Add siblings to an already volatile team and the familial unit becomes a tinderbox. Kids want parents to give them more than their brothers and sisters receive; it is for this reason that whining in some families is elevated to a Homeric art form. We are our brother's competitor as well as his keeper.

No surprise, then, that the emotions propelling children to seek attention can turn deadly. Kids attempt to faze parents with the vices of , including drug and use and reckless behavior. And, arguably, the suicide attempt.

Some percentage of teen suicide attempts have long been considered cries for help, risky gambits that seek to heighten parental concern rather than to truly end a life. Now Paul Andrews, a psychologist at the Virginia Institute for and , has identified a pattern in the behavior of middle-born children that reinforces the idea of teen suicide as just such a last ditch effort to garner parental attention.

Andrews found that middle-borns are less likely than first- or last-borns to attempt suicide, but more likely to actually succeed in killing themselves. Even in a behavioral arena as charged as suicide, argues Andrews, middle-borns need to distinguish themselves with an act that is impossible to ignore. Because their suicide attempts are more extreme, the results are more lethal. And because the bar on parental attention is high relative to their siblings, they don't resort to suicidal gestures as frequently. These children either abstain completely or go all out; there are, ironically, few in-between bids for parental attention among middle-borns.

is a source of pain as well as the most wonderful, keenly felt love and devotion. Mark Twain noted, "When I was a boy of fourteen, my father was so ignorant I could hardly stand to have the old man around. But when I got to be twenty-one, I was astonished at how much he had learned." Being a little slower than Twain, I came to understand my own father better at a much later age.

Cross-generation Communication

Whether you're 16 or 65, you may need help communicating across the vast familial cosmos.

If you are grappling with a difficult child:

Refuse to enter into power struggles. State your position in a forthright way, and allow your family member to make choices for him- or herself. Let him know that your love and respect is not contingent on their agreement with you.

Keep the channels of communication open and respectful. Try actively listening without judgment while encouraging any disclosure. Offer your own heartfelt desires for communication by disclosing your vulnerabilities. This models nonjudgmental and disclosure.

Pay attention to middle-born children. It is easy to assume that they receive equal attention when in fact, they do not.

If you are deadlocked with a parent: