Late one Tuesday night last year, I received an email from a former colleague and friend who recently moved to Brooklyn. It began, “Dear Lord, today, on my block, in my building, on my floor, next door, a baby died. She was 16 and it seems someone decided to cut her throat.”

The next morning she shared with me what was more than just a poem about a dead child. Her light of day details, both graphic and heartbreaking, were about the real young girl who lived next door. A polite young girl she had often seen in passing was, indeed, dead.

My friend’s first hand account was made even more unbelievable as the story played out on my television and in the papers over the next two days. Marva Braithwaite had come home to find her 16-year old daughter Shannon stabbed to death just inside her front door.

The reportedly “remorseless killer” was Shannon’s 15 year old cousin Tiana Browne, a chronic runaway whom the mother had taken in just two days earlier. She was arrested by the NYPD and has been charged with second degree murder. She has also reportedly confessed to the crime.

Made more frightening is that, apparently, Tiana’s heartlessness had no bounds. She had stabbed Shannon at least 18 times and then slashed her throat. Extremely jealous of Shannon, she also reportedly ripped the dying victim’s sneakers off her feet, ignoring the blood spreading across the floor just inside the apartment and stole property belonging to Shannon, including birthday and Christmas gifts, an iPod, a cell phone and a camera. She was wearing the shoes when she was arrested.

How does this happen? Was Tiana “a bad seed who should not have been taken in?” as a relative of Ms. Braithwaite had warned. Who raised this broken child and under what circumstances?

We know a little. “I knew Tiana was a problem child. I knew she was a runaway,” Marva Braithwaite has said in the press. “But I never knew she was planning on killing my daughter…and I never knew she had that much rage in her.”

We also know now from a law enforcement source that in a Family Court complaint last year, Tiana’s own mother had charged that Tiana was mentally ill, a truant and a chronic runaway. They did not return for a January court date and the case was dismissed.

Make no mistake, Tiana isn’t the only ticking bomb that walks among us. According toa recent study of 20,000 teens, 15% are fatalistic, believing that they are going to die young. It is those teens who are more likely to engage in risky behaviour. The study’s author has said that such fatalistic tendencies are not because teens believe they are immortal but actually because “because they feel hopeless and figure that not much is at stake,”

Clinical depression and bi-polar disorders in the minority community, particularly among African Americans, and particularly among adolescents, is a silent and destructive epidemic. In my book Black Pain: It Just Looks Like We’re Not Hurting, I recount several stories of young people suffering from depression. Dismissed, undiagnosed and stigmatized, their distress is exacerbated in urban communities due to shared economic woes, broken families and a history of learned silence. If left undiagnosed and untreated, this emotional and mental distress can become a full blown mental illness

According to the World Health Organization Report on Mental Illness, by the year 2020, depression is projected to become the second largest killer in America behind heart diseases, and will disproportionately affect minority groups. A survey by the National Mental Health Association revealed that only one-third of all persons with major depression ever seek treatment. Within the African American community, it is only 16%.

With overwhelming evidence of the connection between unmet mental health needs and Black-on-Black crime, substance abuse, violence, incarceration, poverty, poor health, foster care, unrealized potential in academic and occupational pursuits, diminished community well-being and deferred dreams, it is urgent that we identify and address this crisis in the Black community. We are dying every day.

During the years, social scientists and mental health professionals like me (I have suffered from my own bout of depression) have sought to identify specific predictors of violent and antisocial behavior. Many of us have concluded that one of these predictors is depression. Early research supports these findings.

According to the National Center for Justice, “the experience of depression during adolescence is hypothesized to be a central pathway through which girls’ serious antisocial behavior develops for several reasons. Although alternative sequencing is possible, researchers hypothesize that depression may influence girls’ propensity toward antisocial behavior. Key characteristics of depression include Post Traumatic Stress Disorder, difficulty concentrating, loss of interest in previously enjoyed activities, hopelessness, feelings of worthlessness, and, at its extreme, suicidal thoughts and tendencies.”

Addressing this issue is of national importance and there has been movement on the Federal level. The Federal Mental Health Parity Act goes into effect for most insurance plans in January of 2010 and requires health insurance companies that provide mental health to provide benefits that are comparable to the benefits provided for physical ailments.

Yet, even in her despair, Ms. Braithwaite knows that something more must be done. At Shannon’s vigil in front of her apartment building, she issued a call-to-action to a gathering of more than 70 friends, neighbors and community leaders. “Do all you can to help our troubled kids or you will be standing where I am today. When a child is messed up, the whole community is messed up,” she said.

She is right. It is up to us. We are born innocent creatures who are shaped by our experiences and by our environment. No one is born bad, mad or evil. We must work to reduce the number of young people (and everyone for that matter) undiagnosed and suffering from depression. We must provide new ways for the community to engage in dialogue and become educated about this insipidly silent disease. If we do not begin now to foster a generation of healed, healthier and better people, there will be many more Shannons and Tianas.

By all accounts Ms. Braithwaite had raised a beautiful girl. With Guyanese roots, Shannon was living the American dream. She was an ‘A’ student at Vanguard on the Upper East Side. She loved singing and dancing. She went to church. It seems Tiana’s mother also tried to do the right thing by trying to get Tiana help. They – and many other young people like them – are both lost to us now, and the rest of us should take note and then take action.