Caroline Peel said she felt dizzy and went up to her bedroom at the house in Bramley with her two daughters downstairs.
But, after hearing a thud above her, little Summer leapt to action and used her mum’s phone to call for help.
The brave youngster also managed to calm down her sister Maisie, seven, who was fearing for her mum’s safety.
Mrs Peel, of Broadlea Terrace, Bramley, said: “I just didn’t feel well so I took myself upstairs and then that’s when Summer said she just heard a big bang.
“Her little sister was asking ‘is mummy dead?’. But Summer calmed her down and called her grandma who came over and rang the ambulance.
“I don’t know what I would have done if it wasn’t for her because they said my blood pressure was really low. She was really brave and fast-acting.”
After her grandmother came to the house, paramedics arrived and Mrs Peel, who recently underwent an operation and was on medication at the time, was rushed to hospital.
And to recognise the quick-thinking youngster’s bravery, her school recently held an assembly following her actions at home on December 27, where she was presented with a teddy bear by the head teacher at Hollybush Primary School.
Mrs Peel, 33, added: “The paramedics told her that she did really well and that she is a brave little girl.
“What she did was amazing.”
Dad Matthew Peel said: “She is very aware and I’m obviously very proud of her.”
Both parents are now trying to raise awareness about what children should do in similar situations.