The former Neighbours actress, who is currently preparing for a stint in Dancing with the Stars, dropped her rehearsal commitments to be with 56-year-old cyclist Andy at Brisbane Hospital after he collided with a car in Mt Coot-Tha during an early morning training session.
McNaught told The Telegraph that her dad fractured four vertebrae in the incident, adding: "As well as breaking his back, he's grazed shoulders, legs, knees, back. He was doing about 50-60km/h when he T-boned the car and flew over it.
"He's also broken his scapula in three places. He's now in a back brace for some months but hopefully will be out of hospital in the next couple of days."
She said that this is not the first time Andy has broken his back, saying: "In the 1990s we were living in Seattle and he was doing a downhill run on his mountain bike. He came off and compressed three vertebrae and ended up in the same brace.
"He was also in a hit and run about eight years ago, but luckily he keeps surviving and with a bit of luck he'll make 57 next week."
Erin later used her Twitter page to warn drivers to take care around cyclists, writing: "My dad is in hospital w/ four fractured vertebrae because a girl did a U-turn across double lines on a blind corner. PLS WATCH FOR CYCLISTS."
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