A Mansfield lorry driver with only one arm has admitted crashing into a car, killing a three-year-old girl and her unborn brother and seriously injuring their mother.
Thomas Hunter, 59, crashed his Volvo articulated truck into the back of a car that pregnant Collette Wiggin and her daughter Isla were travelling in.
Isla suffered serious brain injuries in the crash and died two days later, on August 27, at John Radcliffe Hospital in Headington, Oxon.
Her 31-year-old mother suffered a broken neck and lost her unborn son - whom the family had already named Harry, a name chosen by his would-be big sister.
In a statement the family said Isla was "so excited at the prospect" of a baby brother and "her loving and caring nature would have made her an amazing big sister".
Hunter appeared in the dock with a prosthetic left arm with a hook, at Oxford Crown Court.
He was told by Judge Zoe Smith that he would be sentenced on July 17 following the crash on a busy carriageway in August 2016.
Hunter pleaded guilty to causing death and serious injury by dangerous driving.
The court heard that thirteen other people were injured in the six car pile-up on the A34 at Hinksey, Oxford.
An inquest into Isla's death in September last year heard how the car was in a queue of 'slow-moving or stationary traffic' when it was struck from behind by the lorry.
Prosecutor Michael Roques told the court there must have been a 'distraction' for Mr Hunter to 'miss the traffic jam'.
Mr Roques added that the death of Mrs Wiggin's unborn son, and Mr Hunter crashing into five other vehicles, further aggravated the offence in respect of sentence.
In a tribute to their two children last year, Isla's parents said, "Isla was as perfect a daughter as you could ever wish for.
"Beautiful and witty, yet cheeky and mischievous, she was a character that you couldn't help but love with all your heart."
They added that the family had called their unborn child Harry after their daughter said she liked the name.
"We were extremely proud to find out that we were going to have a son, who would have completed our family.
"He had big hands and strong arms and no doubt would've grown into a strapping young man who would have loved and protected Isla.
"We are so sorry that we didn't get the chance to meet him properly and get to know him.
"Not a day will go by where we won't think of them and all the happy memories that we have shared."
Defending Mr Hunter, Alexander Stein said the defendant was of previous good character.
He added: "He knows exactly what's going to happen."
Hunter was granted bail and told by Judge Smith that he was disqualified from driving before appearing at the same court on July 17.