CHATTANOOGA, Tenn. — A Kuwait-born man who shot and killed five service members in Tennessee was first treated by a child psychiatrist for depression when he was 12 or 13 years old, a family representative said.

The representative, who spoke Sunday on condition of anonymity to avoid unwanted publicity, said 24-year-old Muhammad Youssef Abdulazeez also fought drug and alcohol abuse, spending time in Jordan last year to help clean himself up.

The representative said relatives of Abdulazeez believe those personal struggles are at the heart of last week’s killings at a pair of military sites in Chattanooga.

“They do not know of anything else to explain it,” said the representative, who has been involved with the family since the shootings. The claim fits a pattern of behavior by Abdulazeez that includes a drunken driving arrest earlier this year and the loss of a job over a failed drug test.

Several years ago, relatives tried to have Abdulazeez admitted to an in-patient program for drug and alcohol abuse but a health insurer refused to approve the expense, said the representative.

“He was medicated like many children are. Through high school and college he did a better job sometimes than others staying with it,” the representative said.