The off-duty officer, who has not been named, was driving with his wife when he spotted the toddler near Trent, last Wednesday.
He approached her to ask her where she was going and she replied: “I am going to nursery. I can’t wake mummy up.”
The girl then led him back to her home in Shobnall Road, where her mum, Nicolla Rushton, 30, was discovered dead.
The heartbreaking details emerged yesterday as it was revealed police were not treating the death of Ms Rushton as suspicious.
Chief Inspector Steve Maskrey, from Staffordshire Police, has since praised his officer and said his actions showed police “are never off duty.”
“This is a brilliant piece of work by him that shows that we are never off duty. "The officer and his wife took the time to look after the little girl and stay with her until emergency services arrived. “Sadly nothing could be done to help the woman. “My thoughts are with the family and friends of the deceased at this difficult time. "The little girl is now safe with family.
“I must also praise the community who all came together and helped the police with their inquiries. Thank you.”Nicolla's devastated mother Stacey Inchley was too upset to comment at her home in Stretton, Staffs.
Speaking outside her house, Nicolla's brother Anthony Rushton, 28, said:
"The family just needs time to grieve at the moment. "My mum is absolutely heartbroken and it's too much to talk about at the moment.Staffordshire Police said they were called to the house by colleagues from West Midlands Ambulance Service after Ms Rushton was found, shortly before 11am. She was pronounced dead at the scene shortly after they arrived.
A spokesman for the West Midlands Ambulance Service said:
"An ambulance and a paramedic officer were sent to the scene. “On arrival, crews discovered a woman patient. "Unfortunately, it quickly became apparent that nothing could be done to save her and she was confirmed dead at the scene.”A neighbour, who did not wish to be named, said Ms Rushton was very ‘quiet’, and added:
“She just kept herself to herself. “I am gobsmacked, I didn’t know her that well but from what I saw she seemed very happy and loved her little girl.“She was the quiet type and it is just really upsetting. "It is so shocking when it happens on your doorstep. "It is just awful.”
Another neighbour, who didn't want to be named, said:
"I didn't really know Nicolla. She kept to herself but seemed happy when I said hello to her. "I used to see her taking her little girl to the nursery up the road. "I'm so shocked about what's happened. I left a bouquet of flowers when I heard. "My heart goes out to the family. It's so sad."A report is being prepared for the coroner.