Updated

Linkin Park singer Chester Bennington has died on what would have been Chris Cornell’s 53rd birthday.

The Soundgarden singer hanged himself on May 18, and now Bennington's death is also being investigated as a possible suicide, as TMZ reports he hanged himself, too.

The two performers were close friends and even toured together in 2007 and 2008. Bennington joined Cornell for a version of Temple of the Dog’s “Hunger Strike,” and Cornell performed alongside Linkin Park for their 2000 hit “Crawling.”

LINKIN PARK'S CHESTER BENNINGTON DEAD AT 41 FROM APPARENT SUICIDE

Bennington was also reportedly the godfather of one of Cornell's three children.

Cornell’s widow Vicky tweeted out a message for the 41-year-old's wife Talinda Ann Bentley.

On the day of Cornell’s passing, Bennington wrote a lengthy post via Instagram describing how the rocker impacted him:

Bennington performed Leonard Cohen's "Hallelujah" at the Soundgarden singer's memorial in late May.

TMZ reported Bennington struggled with drug and alcohol addiction and had previously talked about suicide as the result of childhood trauma and abuse.

FRENCH SINGER REPORTEDLY COLLAPSES, DIES ON STAGE

Cornell’s toxicology tests showed the presence of barbiturates, caffeine, and lorazepam, also known as Ativan, for relief of anxiety. The report also listed naloxone, an anti-opioid drug, and a decongestant. However, Dr. Theodore Brown, assistant Wayne County medical examiner, announced the drugs found in Cornell’s body did not contribute to his death.

Bennington leaves behind six children from two marriages.