A four-year-old boy from south London saved his unconscious mother's life by using her thumb to unlock her iPhone and asking Siri to dial 999.
Roman used the phone's voice command technology to call emergency services after fearing his mother had died, telling the operator: "She's closing her eyes and she's not breathing."
He was able to tell the operator his home address in Kenley, Croydon, allowing paramedics to give life-saving first aid to the woman.
The boy, his twin brother and young brother were found inside the property.
The Met Police released the audio of the 999 call, made on 7 March, in the hope other parents will teach their children to memorise their home address in case of an emergency.
Chief Superintendent Ade Adelekan, from the Met's Command and Control Unit, where 999 calls are handled, said:"Hearing this call brings home the importance of teaching your young child their home address and how to call police or emergency services in an emergency situation.
"If you do nothing else today, then I'd implore any parents of young children to sit down with them and make sure they know what to do in this kind of situation and that they know how to contact police or other emergency services in an emergency. As this case demonstrates so poignantly, it could really be the difference between life and death.
"It's an amazing story and thanks to his quick thinking and by asking 'Siri' for help, this little boy saved his mum's life and it means she is still here and can be extremely proud of him and his brothers."