This is the heroic moment a four-year-old boy saved his baby sister from suffocating when a blanket accidentally covered her head.

A baby monitor captured the dramatic moment at a family home in Guangzhou, in China's southern Guangdong Province on the afternoon of October 14.

The five-month-old baby, playing alone, was accidentally covered by a blanket, struggling to breathe for more than 10 seconds.

Luckily, her four-year-old brother immediately ran over and lifted the blanket with both hands, rescuing his sister.

After ensuring the baby's safety, he pulled the blanket away and threw it away, preventing a similar incident from happening again.

According to Mrs. Pan, the mother, she was doing household chores in the living room while keeping an eye on her children through the home surveillance system.

Upon witnessing the incident, she immediately asked her four-year-old son to help his sister.

She said she was very grateful to have such a brave and quick-thinking son.

Mrs. Pan said: 'I am very grateful for my son. He is very brave and smart.

'At the same time, I want to remind other parents never to let their children be in danger due to negligence.'

She stated that she would pay even more attention to her children's safety and urged other parents to strengthen safety education for their own children.