The "battle" that Daryl is referring to is Johnny's fight with cancer, which in an Instagram post in November of last year, the 33-year-old shared the devastating news that his cancer had returned.
“After an unexpected week of seizures and excruciating headaches it is with a heavy heart that i have to let you know i now have another huge battle ahead of me as my brain cancer has returned,” he wrote alongside a photo of himself and girlfriend Tahnee Simms.
He continued: “Though i will dig deep and beat this sh*t disease again #f*ckcancer”.
Johnny's girlfriend Tahnee posted a picture of him attached to a hospital drip in December last year, where she expressed how proud she was of her boyfriend throughout his brave battle.
"Not what we had planned for our Christmas Eve Eve this year but still smiling through it all & feeling as grateful as ever @johnny_ruffo," the 27-year-old wrote.
"You can move mountains #f*ckcancer."
Johnny was quick to thank Tahnee for her ongoing support and love, commenting: "Thank you for everything you do and beyond, I love you more than words can describe."
The actor and singer was originally diagnosed with brain cancer in 2017, and he has previously opened up about how tough it was to hear the diagnosis and later fight the disease.
“It's pretty heavy hitting from the get-go so it's not something that doesn't really sink in straight away. As soon as you hear the news it's like... sh*t,” he revealed of the ordeal in 2018.
“It's been pretty full on. But I think as you go on, you kind of find ways to deal with it a bit more and just develop coping mechanisms.”