A child witness in the Liam Fee murder trial claimed he lost consciousness after one of the accused stood on his neck as he lay on the floor.
The boy said Nyomi Fee, 29, stopped him breathing after kicking and punching him.
He claimed Fee later made her civil partner 32-year-old Rachel Trelfa – Liam’s mum – join in on one occasion.
He said: “I was lying on the floor getting smacked and punched and she (Nyomi) put her foot on my neck and it made me unconscious for a while.
“I was choking and I couldn’t breathe. It was sore. When I woke up she was punching me on my back because I must have done something but I don’t know what.
“When they both did it it was extra sore,” he said.
The boy revealed details of the abuse during a filmed interview with a police detective and a social worker which was shown to the jury at the High Court in Livingston on Friday.
He demonstrated what had happened by pressing both hands to his throat.
On another occasion he said he’d been tied up in a cot and Nyomi caught him trying to escape.
He said she was angry that he’d been able to get out and she made him climb into a drawer.
She put wire mesh, a wheelchair and a Hoover on top of him to stop him from escaping again, he said.
Rachel Trelfa and Nyomi Fee deny murdering two and a half year-old Liam at a house near Glenrothes in March 2014.
They also deny wilfully neglecting and harming two other boys.
The trial before Lord Burns continues.
