Hoole toddler Isaac Gregory is only five-years-old, but you’d be forgiven for thinking the little boy is much older, because of the way he has conducted himself in some very challenging family circumstances.

Just before his first sister Isabelle was born when he was two, Isaac’s parents Jemma and Craig were devastated to learn during a routine scan that their unborn daughter had severe brain abormalities and may not survive the birth.

When she was born a week later, weighing just 4lb 7oz and struggling to breathe, none of the family knew if Isabelle would survive or not.

It was a difficult time for all the family, but despite his young age, it was Isaac that turned a three-week stay at Alder Hey Children’s Hospital into an adventure, lifting everyone’s spirits by making sure there were always lots of smiles to go around.

Isaac Gregory who has been nominated by his mum for a national Super Sibling Award

When Isabelle was well enough to go home, Isaac didn’t hesitate in helping to feed his sister, change her and sing to her when she was ill.

Sixteen months later, when Isaac was four, his second sister Imogen arrived and had to spend a difficult 17 days in the special baby care unit at the Countess of Chester Hospital.

Once again, the proud big brother took it all in his stride and showed extraordinary understanding of the situation from the start.

Jemma, 34, remembers: “The first time Isaac met Imogen she was in an incubator. If you watched him you’d think this was all familiar to him - he understood that babies in the incubators were poorly and he needed to be quiet. He wasn’t fazed by the alarms, the wires, the big machines or the nurses watching him creep in. As he peered his head over the side of the big transparent box, he beamed and said: ‘Hello Imogen’.

“He looked past the tubes and wires to see his beautiful tiny little sister. We spent a lot of time there and he kept us laughing,” she says.

And it is because of Isaac’s astonishing maturity at such a young age that Jemma has nominated her son for a Tommy’s Award for being a Super Sibling, which recognises individuals who make a difference to families, in particular those whose lives have been touched by pregnancy complications or the loss of a baby.

Jemma adds: “I nominated Isaac for the Super Sibling Award because people tell us we are strong and brave, but Isaac is the one that has kept us all smiling, that has kept us strong even on the darkest days and is the young hero in our little family.

“His sisters are so different but he’s brilliant with both of them. He’s helping Imogen to walk and talk. Isabelle is severely disabled and he has his own understanding of why Isabelle has a tube in her tummy and that she has a broken brain and is very brave.

“He reads her stories, strokes her hair when she is sad and knows how to make her smile.”

Jane Brewin, chief executive of Tommy’s, said: “Isaac and his family have been through so much together and it’s clear that Isaac has taken everything in his stride and shown love, care and humour in some very challenging circumstances.

“We were incredibly touched by Jemma’s nomination and we’re delighted to shortlist Isaac for the Tommys and Center Parcs Super Sibling Award.”

The winners will be announced at the Tommy’s Awards in a star-studded ceremony at the Landmark Hotel, London, on Friday, March 20.