Naya Rivera's 4-year-old son Josey told investigators with the Ventura County Medical Examiner’s office that before the star disappeared into the water and drowned on July 8, they counted "1, 2, 3" and jumped off the pontoon boat together at Lake Piru, reports say.

The Glee star's full autopsy and investigative reports were obtained Friday (September 11) by People. After jumping, Rivera then told Josey to get back on the boat. Then tragedy struck.

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"She helped him onto the boat and then he then heard [Naya] yell 'help' and she put her arm in the air. She then disappeared into the water," the investigative report states, People writes.

While Rivera was in good health, she had a history of vertigo that would cause complications and get worse when she was in the water, officials note in the report. She had been treated for vertigo prior to her death.

Additionally, Rivera had been prescribed adderall for anxiety and had been taking medication for a sinus infection, the report says.

Rivera, who shared Josey with ex-husband Ryan Dorsey, was also "considered to be a good swimmer," the autopsy report states. The cause of death remains drowning and the manner of death was ruled an accident.