Little Aaron Green somehow managed to call his great-grandmother when his mother Cally, 26, had a diabetic seizure.
The barmaid, from Coventry, West Midlands, had just finished a night shift at when she returned home and was gripped by a hypoglycemic attack which caused her to collapse.
Little Aaron found her the next morning lying on the floor of her bedroom and was unable to wake her.
The little boy – who does not yet know the alphabet and can only just count to ten -reached for his motherâ€™s Blackberry phone which was lying on her bed.
It is thought he knew what to do with the phone by watching his mother use it.