Authorities have revealed the cause of death for the California family mysteriously found dead with their dog along a hiking trail in the Sierra National Forest in August. In a press conference on Thursday, the Mariposa County Sheriff's Office confirmed that John Gerrish, Ellen Chung and their 1-year-old daughter Miju died of hyperthermia and probable dehydration. Their 8-year-old dog Oski also suffered a heat-related death, police said. Subscribe to People ►► http://bit.ly/SubscribetoPeople #JohnGerrish #EllenChung #PEOPLE Catch up on the latest celebrity news, top stories and more: https://www.youtube.com/watch?v=6wQfUfqL8Ms PEOPLE goes behind-the-scenes with our cover stars for exclusive stories and in-depth interviews: https://www.youtube.com/watch?v=OQKl_X701vU PEOPLE goes in-depth with your favorite stars and celebrities to bring you exclusive stories and features: https://www.youtube.com/watch?v=_9H8u-Cso1s Go inside the homes of your favorite celebrities with exclusive house tours: https://www.youtube.com/watch?v=i7e1ouxAzTA Get exclusive access into the biggest celebrity weddings. From the dresses and rings to dances and surprises, PEOPLE covers it all: https://www.youtube.com/watch?v=3m_c4GsTEpY Watch as your favorite couples reveal the secrets to love and happiness in celebrity love stories: https://www.youtube.com/watch?v=r1TfoQhG0WQ Stay up to date with The Royal Family: https://www.youtube.com/watch?v=BAmSICLYVCE Watch kids interview your favorite celebrities with the most adorable questions you'll ever hear: https://www.youtube.com/watch?v=N4bfeRdCE1E ABOUT PEOPLE PEOPLE remains the trusted authority at the center of pop culture. The PEOPLE brand features a unique mix of breaking entertainment news, exclusive photos, video, unparalleled access to the red carpet, celebrities, and in-depth reporting on the most compelling newsmakers of our time. CONNECT WITH PEOPLE Web: https://people.com/ Twitter: https://twitter.com/people Facebook: http://facebook.com/peoplemag Instagram: https://www.instagram.com/people/ Cause of Death Revealed for Calif. Family Who Mysteriously Died on Hiking Trail | PEOPLE null