Brad and Jordan Lewis

Brad Lewis and his son, Jordan, in an undated photo. After Jordan's suicide, Brad posted a plea on Facebook: “This bullying has to stop. People have to stop treating other people the way they do." (Handout photo)

An Illinois dad got the call on Thursday that no parent ever wants to receive.

Brad Lewis' ex-wife was on the phone: Their 15-year-old son had shot himself in the chest.

In the note Jordan Lewis left behind, he laid blame on bullying.

Although stricken with grief, Lewis, 47, found resolve. He took to Facebook that night and posted a series of videos explaining his son's death and the events leading up to it: the alleged bullying, the concern of his son's best friend, the wellness visit by police the night before the suicide, and the 911 call his son made shortly before pulling the trigger. His mission isn't vengeance, he said, but justice — for his son and for victims of bullying from across the country.

"This bullying has to stop. People have to stop treating other people the way they do," Lewis said into a webcam from his Collinsville, Ill., home. "Because some people just don't have the strength to overcome the humiliation, the continuation of being picked on constantly every day to the point that they have no out."

Jordan's death comes as the nation is following several high-profile cases in which children committed suicide after persistent bullying by peers. In September, 12-year-old Rebecca Ann Sedwick jumped from a silo at an abandoned cement plant in Lakeland, Fla., after police say she endured repeated taunts by peers in school and on social media.

Jordan, a sophomore at Carterville High School, cheered for the Chicago Bears and played video games. He had always played football — and he played for the Carterville Lions during his freshman year. But he quit after the first day of practice this year, his father said.

Lewis, who lives about a two-hour drive northwest of Cambria, Ill., where his son and ex-wife lived, talked to Jordan about why he left the team.

"You wouldn't understand, Dad," Jordan said. "I'm being picked on at school."

At the time, Lewis told his son how he himself had once been the target of bullies for having glasses and red hair. He then told his son to report bullies to the principal or his teachers.

In 2008, Yale University researchers compiled studies into the effects of bullying and found that children who were subjected to bullying were between two and nine times more likely to commit suicide.

Jordan, according to his father, was pushed into lockers and hit at least once in the head by a football teammate.

Lewis said that on Wednesday — the day before his son's death — his son watched an anti-bullying video at school.

"At the end of the video, the kid that was being bullied went home and killed himself," Lewis said, adding that police are investigating how Jordan, who lived with his mother, got ahold of a gun.

Jordan had, however, texted a friend that he was considering hurting himself. The friend, alarmed, told her grandmother — who tried contacting Jordan's parents but eventually called police, who made a wellness visit Wednesday night, Lewis said.

The next morning, after his mother left for work, Jordan called 911 and pointed the gun at his heart.

Lewis worries that his son felt hopeless and lost, and that the video at school may have swayed him to send a message. Thursday was Spirit Day — a national effort to raise awareness about bullying — and October is National Bullying Prevention Month.

"My son knows me well enough, that if he couldn't get anything accomplished, I could take on what he wanted stopped," Lewis said.

In the wake of Jordan's death, school administrators have told Lewis that they didn't receive any reports about poor treatment directed at Jordan. Calls to Carterville High School and the Carterville School District were not immediately returned.

His son's death was the impetus, but Lewis said he has become frustrated by the steady reports of teens ending their lives because of mounting torment by bullies.