Songwriter and musician George Young has died at 70.
Young, who was the eldest brother of AC/DC’s Angus and Malcolm Young, was a member of band The Easybeats and co-wrote their hit song 'Friday On My Mind'.
He also wrote John Paul Young's classic 'Love Is In The Air' with his song writing partner Harry Vanda. The pair also penned hits for Meatloaf and Stevie Wright.
AC/DC have paid tribute to Young in a message posted on their website.
“It is with pain in our heart that we have to announce the passing of our beloved brother and mentor George Young. Without his help and guidance there would not have been an AC/DC,” the statement reads.
“As a musician, songwriter, producer, advisor and much, much more, you could not ask for a more dedicated and professional man.
“As a brother, you could not ask for a finer brother. For all he did and gave to us throughout his life, we will always remember him with gratitude and hold him close to our hearts.”
Jimmy Barnes paid tribute to the late musician on Twitter writing: "George Young RIP What a huge loss for music. A great songwriter, producer and a great human being".