husband, Ciaran, rushed to the scene.
However, his wife died after the accident, while their baby was rushed to hospital by emergency services.
Locals in Balbriggan, where Olivia was well known, were left reeling as word spread of the single vehicle accident.
The incident occurred shortly after 12.30pm just at the entrance to the Balbriggan Retail Park, near the White Hart Inn, within a short distance of Olivia's home.
Onlookers said the car, which was travelling southward towards Balbriggan just before the impact, ploughed into the railings at the entrance to the retail park.
The baby was rushed by ambulance to Temple Street Hospital and was last night in a serious condition.
It is understood that the child had surgery for kidney damage at Temple Street hospital and was also treated for a broken leg.
Meanwhile, the driver of the vehicle, a Ssang Yong Kyron small people carrier, was also taken to hospital with non-life threatening injuries.
Olivia's husband, Ciaran, along with his mother, remained with his wife's body until the remains were taken away by ambulance for post mortem.
The four month old baby was the only child of Oliva, who had recently qualified with a Masters degree and was originally from Skerries.
Her parents are Margaret and Seamus Clinton and she is also survived by a sister, Marguerite, who runs a dancing school.
It is understood that she was a teacher, but was currently on maternity leave after the birth of her baby last autumn.
Ciaran, is originally from the Hampton Cove area of Balbriggan.
The couple had married in July 2012 and it is thought that they had only moved into the Balrothery area after their marriage.
Local people in Balrothery were in shock over the tragedy yesterday, saying Olivia had been a familiar figure out walking with her baby.
She had been a "lovely lady" and was always very friendly, they said.
"I can't believe it," one neighbour who knows the Clinton family for many yearssaid.
"She was such a lovely person and was over the moon when her baby was born." One local man said the stretch of road where the accident had taken place was "an awful road".
"A young girl was killed on New Year's Eve just a few hundred yards away," he said..
"I'm totally shocked. My heart goes out to the family."
Local parish priest Fr Eugene Taaffe was last night on his way to visit the family and did not wish to say anything about the tragedy.