Roman realized that he needed to get help, but how?
"It later emerged that the boy used his mum's smartphone to get in touch with police. He firstly managed to unlock it by pressing her thumb on the phone and then used the 'Siri' function to ask for help and it dialed 999 to put him through to emergency services," said the police. 999 is the UK's emergency number.
The police released a recording of Roman's phone call with the emergency dispatcher. On it, he explained that his mom was "dead."
When the dispatcher asked what he meant, he replied: "It means she's closing her eyes and she's not breathing."
The dispatcher managed to get Roman to tell her his address. Police and paramedics arrived at Roman's house 13 minutes later, broke in and began to administer first aid. His mother regained consciousness at home, the police said, before being taken to hospital.
The lesson is that it's worth teaching your kids what to do in an emergency.
"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," said Superintendent Ade Adelekan of the Metropolitan Police.
"It's an amazing story," Adelekan added, "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."
Apple didn't immediately respond to a request for comment. However, CEO Tim Cook heard about Roman and posted this to Twitter on Friday: "Incredible story, courageous boy. Well done, Roman! We pray for your mom's speedy recovery."
One can only imagine what Roman's mother must think every time she looks at him -- or her phone.
First published March 23 at 10:20 a.m. PT. Update March 24 at 4:01 p.m. PT: adds reaction from Tim Cook.
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