A Perth family is grieving the loss of their young children following a horrific crash outside Geraldton in Western Australia's Mid West yesterday.
Nate Stewart, seven, and Harmonie Cunningham, 10, died when the car in which they were travelling hit a utility on Monday afternoon.
The Perth family had been holidaying in the region over the WA Day long weekend and were on their way home when the accident happened.
The children's aunt, Ashlee Cunningham, said the family was in "a horrible state of disbelief and pain".
"They were two of the most beautiful children, loved by so many," she said.
"Nate could light up a room with his cheeky dimply smile and Harmonie was just so thoughtful beyond her years, she would have you in laughs with her beautiful imagination.
Grief-stricken grandmother Debbie Cunningham also paid tribute to the children.
"Harmonie is an absolutely beautiful person, everybody loves her, everybody who comes into contact with her," Ms Cunningham said.
"[She's] always bubbly and smiling and laughing and jumping around, an absolutely beautiful little kid, and loved her brothers and sisters.
"She absolutely adored her Nanny, she would do anything for me, she wouldn't leave if she could. Nor would Nate — I'm his step-nanny but he loved me too, he's a beautiful little man.
"He loved bike-riding and he was just gorgeous and just loved me too, every minute they were just telling us how much they loved us.
"I just miss them so much, I hope they're just happy and safe, and OK up there."
The sedan in which the children were travelling was hit by a utility at the intersection of McCartney Road and Edward Road in Georgina, about 20 minutes from Geraldton.
The children died at the scene, while the driver and front seat passenger of the sedan suffered minor injuries.
A man in his 30s who was also in the sedan was badly injured and has been flown to Perth, where he remains in Royal Perth Hospital in a serious but stable condition.