A toddler was crushed to death by an electric car seat because his mother's boyfriend was annoyed that he was making too much noise, a court has heard.
Three-and-a-half-year-old Alfie Lamb was in the rear footwell of an Audi car when he was squashed "at the touch of a button" in February last year, the Old Bailey was told.
Stephen Waterson, 25, who was in the front passenger seat, allegedly pushed his seat back twice in anger at the "noise and fuss".
Alfie's mother, Adrian Hoare, 23, who was in the seat behind her son, is charged with manslaughter alongside Waterson.
The driver, Marcus Lamb, 22, and his then-girlfriend Emilie Williams, 19, who was in the back with Hoare, are due to give evidence against them.
Prosecutor Duncan Atkinson QC said a pathologist found the 3ft tall "smiley boy" died from crush asphyxia.
He said: "It was caused by the front passenger seat of the Audi vehicle, Waterson's seat, being moved back further into the rear passenger side footwell at a time when, as was known, Alfie was in that footwell.
"In effect, he was squashed by the car seat and suffocated. This movement of the seat was a deliberate action by Waterson who knew that Alfie was there and was angered by the noise and fuss that the three-and-a-half-year-old was making during the fateful car journey.
"The deliberate movement of the seat, by electrical operation by the touch of a button and involving the application of considerable force to Alfie, took place not once but twice.
"Waterson was prevailed on to move the seat forward again because it became immediately obvious that it was causing Alfie breathing difficulties.
"However, when Alfie made noise again, Waterson deliberately moved his seat back again, and kept it in that reversed position, squashing Alfie, as he again showed signs of breathing problems until he went ominously quiet."
Hoare had a duty of care to Alfie but did "nothing" to help him, Mr Atkinson said.
Both defendants went on to lie to police about what happened, the court heard.
An ambulance and police had been called to Adams Way in Croydon, south London, to a report of an unresponsive child on the evening of February 1 2018.
Mr Atkinson said it was immediately obvious that Alfie had been dead for some time, even though Mr Lamb was carrying out CPR.
Hoare allegedly told the paramedics: "We got into a taxi and put him into a child seat and he fell asleep. We tried to wake him and found him unresponsive."
She said the taxi driver had "kicked us out" and left.
Mr Atkinson said it was "only the beginning of the lies that she, and others, were to tell".
Police found CCTV footage which showed that Hoare, Miss Williams, Mr Lamb and Waterson had all travelled together to Adams Way in a dark Audi car.
Mr Atkinson said: "It was during that car journey that something happened to Alfie that compressed his chest and/or abdomen so that he went from an active toddler to a very seriously ill and brain-damaged one."
Since then the other occupants of the car had been attacked, Miss Williams by Hoare and Mr Lamb by Waterson, the court heard.
Hoare denies manslaughter, child cruelty and common assault on Miss Williams.
Waterson has pleaded not guilty to manslaughter and intimidation of Mr Lamb.
The couple, from Croydon, and Williams have pleaded guilty to conspiring to pervert the course of justice by making false statements to police.