A man said he would “not be told what to do by a three-year-old” as he crushed his girlfriend’s son with a car seat, a court has heard.
Stephen Waterson, 25, is accused of twice pushing the front passenger seat of his Audi convertible into Alfie Lamb, who was in the footwell behind.
The boy’s mother, Adrian Hoare, 23, told the Old Bailey Mr Waterson got “annoyed” after saying he did not have enough space for his legs.
Both deny manslaughter.
The pair and Alfie were in the car with two other adults and another child during the journey from Sutton to Croydon on 1 February last year.
Giving evidence, Ms Hoare said Alfie was “irritable and tired” after the shopping trip and made it known he was uncomfortable in the rear footwell of the Audi.
She told the jury he called out “mummy” when Mr Waterson first moved his chair back, and Ms Hoare asked her partner to shift forwards again.
The hairdresser said he got annoyed, shouted at the boy and “told him to shut up” which “scared” her son.
“After he said that he did not have room for his legs, he made another comment along the lines he was not being told what to do by a three-year-old because we asked for the chair to be moved, and he moved his chair back again,” she said.
Ms Hoare, who is accused of not doing anything to help her son, told the court she never thought Alfie was in danger and thought he had gone to sleep when he went quiet.
When they arrived at Mr Waterson’s flat in Croydon, they found the three-year-old had gone floppy but “everybody thought he was playing to start with”.
Ms Hoare denies manslaughter, child cruelty and common assault on Emilie Williams, who was also in the car.
Mr Waterson denies manslaughter and the intimidation of the car’s driver Marcus Lamb.
The couple and 19-year-old Ms Williams have pleaded guilty to conspiring to pervert the course of justice by making false statements to police.
The trial continues.