Depression and anxiety have many different causes. For me, I’m pretty sure I came out of the womb with a chemically imbalanced and anxious brain. For others, they live their lives completely mentally healthy and then, one day, a traumatic event forever alters the chemistry of their brains.

Since March 17, three people likely suffering from post-traumatic stress disorder (PTSD) lost their lives to suicide — two survivors of the school shooting in Parkland, Fl. and the father of a Sandy Hook shooting victim.

Most recently, on Monday morning, Jeremy Richman, 49, was found dead in an apparent suicide. His daughter, 6-year-old Avielle, was among the 26 children and staff killed in the 2012 Sandy Hook Elementary School shooting.

Jeremy was an advocate for better research of violence triggers in the brain, and he also spoke openly about his own mental health struggles. He started The Avielle Foundation a few months after his child's death and told NPR in 2017 that his dream was to foster a shift "in the way society views the health of the brain."

"(The brain) is just another organ that can be healthy or unhealthy, just like heart disease or cancer or diabetes," he said.

The Avielle Foundation released this statement on their Facebook page yesterday afternoon:
"Tragically, (Jeremy's) death speaks to how insidious and formidable a challenge brain health can be and how critical it is for all of us to seek help for ourselves, our loved ones and anyone who we suspect may be in need."

Nineteen-year-old Sydney Aiello —  a girl who enjoyed cheerleading, yoga and wanted to work in the medical field to help those in need —  was the first to take her life. She was a senior at Marjory Stoneman Douglas High School when a gunman killed 17 students and staff, including one of her close friends. Sydney lost her life to suicide on Sunday, March 17.

Her mother, Cara, said that, for the last 13 months since the shooting, Sydney had been experiencing survivor's guilt and was diagnosed with PTSD. Cara told CBS Miami, "Sydney struggled to attend college classes because she was afraid of being in a classroom and was often sad recently but never asked for help before she killed herself."

Today, police identified Calvin Desir, 16, as the second Parkland student to lose his life to suicide. He died on Saturday. Calvin was a sophomore at the school and wanted to be an engineer someday.

His sister, Brittany Wright, wrote on GoFundMe, "He was one of a kind, very soft spoken and never once hurt a fly. ... His selflessness and quick action to help others is something that we all deeply admired."

Andrew Pollack, whose daughter Meadow died in the shooting, spoke up about these three suicides. He wants to help prevent this from happening to anyone else.

He told the Miami Herald, “Killing yourself is not the answer. … If anyone feels like they have no one that can understand their pain, if there’s any student out there that’s having a hard time, please reach out to me on Twitter (@AndrewPollackFL). I understand you. You aren’t alone.”

The National Center for PTSD estimates that 28 percent of those who have witnessed a mass shooting develop PTSD and about one-third develop acute stress disorder. Some students at Parkland, Fl. said they never received the tools to manage the trauma they had just experienced or the time to effectively grieve.

Student Kyra Parrow tweeted that, when attending class two weeks after the shooting, "I remember at one point I couldn’t bear to write my paper. I went to my teacher; she proceeds to tell me to put my grief in a box to complete it."

But, if you have gone through a trauma, don't just "put it in a box!" Talk about it. Let yourself grieve. Seek help.

Whether it was a shooting, sexual/physical abuse, a natural disaster, an accident, etc., you can't be expected to just "move on." Traumatic stress has been proven to alter the chemistry of your brain's amygdala, hippocampus and prefrontal cortex. So it's imperative that you check up on your mental health.

Dr. Kelly Posner, a Columbia University professor who studies suicide prevention, told Mother Jones that the best way to combat the symptoms of PTSD is early identification. Some of the symptoms include:

•  Changes in memory and concentration
•  Flashbacks and nightmares
•  Difficulty sleeping
•  Exaggerated startle response
•  Easily irritated
•  Persistent negative beliefs/blame of self, others or the world
•  Self-destructive behavior

Life is hard enough as it is. For me, I haven't gone through anything particularly traumatic, yet I still deal with mental illness. But you - you went through something horrific. Don't ever think there is something wrong with you for the way you are feeling. After what you've been through, how your feeling is to be expected.

So seek help from a trusted family member or friend or talk to a medical professional. Getting the assistance sooner rather than later can help your symptoms from getting worse.

If you or someone you know is at risk for suicide, call the National Suicide Prevention Lifeline at 1-800-273-8255, or text 741-741.