Naya Rivera called out for help before she accidentally drowned while boating with her son at Lake Piru in July, according to an investigative report obtained by Fox News on Friday.

The Ventura County Medical Examiner released the full report along with the autopsy report, which details the “Glee” actress’ final moments after she assisted her 4-year-old son, who was later found sleeping alone on the vessel wearing a life vest, up onto the rental boat.

According to the investigative report, before the accidental drowning, Rivera's son Josey said he and the star "counted '1, 2, 3' and then jumped off the boat together."

Not too long after, Rivera told her son "to get back on to the boat," according to the report.

'GLEE' STAR NAYA RIVERA DEAD AT AGE 33 OF ACCIDENTAL DROWNING, AUTOPSY CONFIRMS

"She helped him onto the boat and he then heard [Rivera] yell 'help' and she put her arm in the air. She then disappeared into the water," according to the report.

BEVERLY HILLS, CA - OCTOBER 21:  Actress Naya Rivera attends ELLE's 20th Annual Women in Hollywood Celebration at the Four Seasons Hotel Los Angeles at Beverly Hills on October 21, 2013 in Beverly Hills, California.  (Photo by Frederick M. Brown/Getty Images)

Naya Rivera died of accidental drowning in July.  (Frederick M. Brown/2013 Getty Images)

Furthermore, the official autopsy report indicates Rivera, 33, “was considered to be a good swimmer,” and according to a lake attendant who rented her the boat, Rivera had declined a life vest, but he included one for her anyway.

In the report, the medical examiner determined via toxicology that Rivera had a small amount of prescribed amphetamines in her system, but did not identify physical conditions or drugs as factors in her death. She had previously dealt with vertigo problems and had a recent sinus infection, the conclusion revealed.

NAYA RIVERA 911 AUDIO, SURVEILLANCE VIDEO RELEASED

Toxicology tests also showed Rivera had small, trace therapeutic amounts of the anti-anxiety drug diazepam and the appetite suppressant phentermine in her system.

In addition, there was "no known history of suicidal ideation or attempt,"  according to the autopsy report.

Rivera's cause of death remains a drowning and her manner of death an accident, the report states.

On July 13, Rivera’s body was located five days after her disappearance floating in an area of the lake that is about 30 feet deep. The Ventura County Sheriff's Office said she was most likely trapped in thick vegetation underwater for several days before floating to the top.

Josey was immediately reunited with his father and other relatives.

The day before her death, Rivera tweeted a photo of the two of them that read, “just the two of us.” In her memoir, she called him “my greatest success, and I will never do any better than him.”

AUTHORITIES RELEASE UNDERWATER FOOTAGE OF LAKE WHERE NAYA RIVERA WENT MISSING, CALL CONDITIONS 'VERY DIFFICULT

Naya Rivera and her son Josey Hollis Dorsey.

Naya Rivera and her son Josey Hollis Dorsey. (CHRIS DELMAS/AFP via Getty Images)

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Rivera was laid to rest at Forest Lawn Memorial Park in Los Angeles two weeks after her death on Friday, July 24, according to a death certificate obtained by People magazine at the time.

The Associated Press contributed to this report.