The boy was tied to a washing line after the women allegedly caught him with dagga and wanted to punish him.
A neighbour who found the shivering child sitting on a cold cement floor in their backyard in Umbrellabird Street, New Horizon on Tuesday alerted cops by flagging down a patrolling police van.
Police spokesperson, Siyabulela Malo, says the resident showed cops a video of the boy sitting tied up in the backyard.
The frantic boy was bleeding as the wire had cut into his wrists and ankles.
The mother, 33, and 57-year-old grandmother are expected to make their first appearance at the Wynberg Magistrate's Court on Thursday.
“Grassy Park police can confirm the arrest of two female suspects, aged 33 and 57, on charges of assault with the intent of grievous bodily harm (GBH) at Umbrellabird Street, New Horizon,” Malo says.
“According to information, members were shown a video of a 12 -year-old minor tied up with wire to a washing pole.
“The video was shown by a concerned community member and members rushed to the scene and rescued the minor, who was helpless.
“Circumstances and the motive behind the assault are unknown.”
A police source reveals the boy had apparently been found with dagga and that his ouma and mother wanted to teach him a lesson.
“The area is called Karara in New Horizon,” says the source.
“The mother and grandmother tied the child up with draad to teach him a lesson because he was found with dagga. The wire made cuts on his body.”
The child has since been placed in a place of safety.