In a statement yesterday, Johnny's family confirmed the sad news.
"He was a very talented, charming and sometimes cheeky boy," they wrote. "Johnny was very determined and had a strong will. He battled all the way to the end and fought as hard as he could. Such a beautiful soul with so much more to give."
Celebrities and fans flooded the post with comments, with many current and former Home and Away stars expressing their sadness.
Lynne, who has played Irene Roberts on Home and Away since 1993, shared a special bond with Johnny, and paid tribute to him in an emotional Instagram post.
"He was our friend and we loved him. But more than that he was a beloved son to Jill, a soulmate to his darling Tahnee, a brother to Michael, a cousin, and a precious grandson to his dearest Nonna," Lynne wrote.
"He fought like a warrior and was brave and cheeky to the end. Talented, funny, loyal and naughty - we love you, my friend. Fly high free from pain. You are missed."
Johnny's partner Tahnee sends love to Lynne McGranger
With Lynne's post also being flooded with comments, Johnny's fianceé Tahnee left an emotional reply to Lynne's tribute.
"❤️❤️❤️ & my did he love you Lynney!!!," she wrote. Lynne was quick to reply, saying "Sending strength and love to you darling girl. Talk very soon. Huge hugs to Jill and Michael."
Former Home and Away actress Sam Frost also expressed her sadness.
"Oh Lynnie, I thought of you as soon as I heard the news. Lots of love to you," she wrote, with current co-star Georgie Parker also commenting "Love to you, Lynne."
Other Aussie stars also sent Lynne their love.
"You were a great friend Lynne," Kylie Gillies commented. "And you have written the most beautiful words to those who loved him hardest. Thinking of you all."
"I know how much he adored you," Rhonda Burchmore said. "And you were such a great friend to him."
Johnny's cancer battle
The singer and former Home and Away star, who shot to fame on the 2011 season of The X Factor, first revealed his health struggles in 2017 after he underwent surgery for a brain tumour, before undergoing chemotherapy and radiotherapy.
Johnny was declared cancer-free in 2019. Sadly, his cancer returned, and he revealed it was terminal in August 2022. He published his book No Finish Line in 2022.
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