But incredibly, this time last year the brave toddler was fighting for her life at London's Great Ormond Street Hospital, during a five month ordeal strapped to an artificial heart and waiting for a life-saving transplant.
Speaking to The Chronicle on Tuesday at her Goring home after dropping Ellie at school for the first time, proud mum Debbie Bolton said: 2It was really brilliant, she has gone through an awful lot and was so excited. She talks a lot about making new friends and sharing toys and she will actually get a chance to do that now."
Ellie, who has a weaker immune system than most children, had her start at Wallingford's Mongewell Park Nursery postponed three times by an outbreak of chicken pox among her future classmates.
Her incredible tale of survival began 18 months ago, when she was taken by her worried parents to their GP and referred to the Royal Berkshire Hospital with a possible chest infection. Doctors quickly diagnosed dilated cardiomyopathy - a condition which causes weakening of the heart and is thought to have been caused by a virus - and rushed to Oxford's John Radcliffe Hospital.
Attempts to stabilise Ellie's condition with medication failed and on February 11 she was put into an induced coma and transferred. Within half an hour of arriving at Great Ormond Street, Ellie was placed on the transplant waiting list and attached to a Berlin Heart - a pioneering machine which helps children survive by keeping blood pumping around their systems.
One in four children die waiting for a transplant, with organ donor numbers declining and the ever present risk of fatal infection. Ellie suffered multiple infections as well as blood clotting - one of which went undetected and caused a stroke - and left the hospital just once during her stay. Debbie remained in London throughout.
Debbie and Ellie's dad, Simon Beale, had five months of uncertainty not knowing if a heart would become available. She said: "You start to think, maybe she is not going to be one of the lucky ones. When we went from Oxford to London, we stopped in Goring on the way and I saw her empty cot. I didn't know if she would ever come home."
Debbie, who agreed to appear on BBC Two's Great Ormond Street documentary series on Tuesday to highlight the importance of organ donation, added: "Since she got home, she certainly does not look like a child who is ill. She has so much energy, it is absolutely lovely to see."