Samuel Johnson's older sister Hilde Hinton shared the shocking news on Monday that her brother had been hit by a car on Saturday night and is in hospital.
Hilde shared the news to Sam's Love Your Sister charity Facebook page, writing, "I wish I didn't have to tell you this. Early Saturday night Sam was on his way to visit family when he was accidentally hit by a car.
"Our Ambos got him picked up and tucked away safely in hospital in record time. I followed them in."
She continued, "The fantastical medical staff are in overdrive taking care of his sore head. He's awake and not too happy that he doesn't have his pants - nobody loves a hospital gown. Hearing his voice is lovely, but can't wait for hugs when it's safe.
"I'll keep you updated."
Sam was also in hospital last month after having surgery on his ear at the Royal Victorian Eye and Ear Hospital.
Fans shared their well wishes in the comments with one user writing, "Oh no, way too much time in the hospital lately, rest up and get better. Thank goodness for our amazing emergency personnel and the wonderful nursing staff, who I'm sure he will eventually have in fits of laughter."
"Sam so sorry to hear of this accident," another wrote. "Rest up and let the doctors look after you. You’ll be back on your feet in no time. Much love to you and your amazing, beautiful family."
"Oh no!" someone else wrote. "So sorry to hear of Sam's accident. Speedy recovery Sam! And big love to you Hilde, being the big sister who always looks out is a very tough gig."
The Eden actor started Love Your Sister in 2012 when his late sister Connie Johnson was diagnosed with breast cancer. Connie sadly passed away in 2017.
Speaking of his sister's passing 2018, Sam said he'd had a long time to grieve before Connie had even died.
He added that one of the things that felt most uncomfortable was "monetising her death" when they were raising money as she was dying.
"I think I did most of my grieving before she died," he told ABC's 7:30 Report.
"I've been grieving for years, since I found out that she was terminal. And she still has her fingerprint all over nearly everything that I do professionally and I pretty much live to work."
"Monetising her death was the trickiest part. I have always struggled to monetise her illness let alone her passing. You know, at that point you don't really want to shake the tin, but it was very important that we do that. That was what Connie wanted.
"She wanted to - you know, to use her experience to help - you know, kind of raise as much coin as possible for our country's best scientists."
Sam was awarded the Australian of the Year honour for his work as an actor and his charity work.
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