Grace, Isabella and Amelia Dunn were born 11 weeks early, weighing just 966g, 1174g and 1293g respectively.

But the three-year-old girls have overcome adversity to embark on a new journey as they start preschool.

"It was exciting for them, but also a big thing for us with all three going at once," mother Nicole Dunn said.

"They were very excited to go.

"If they had have been teary, I would have been the same.

"They're just the best of friends."

The girls were born 11 weeks early at the Royal North Shore Hospital in Sydney, after being conceived on the family's 22nd cycle of IVF.

Mrs Dunn's water broke on Mother's Day and she gave birth via an emergency caesarean the next day.

The triplets spent five weeks in intensive care

Grace and Amelia were on continuous positive airway pressure (CPAP) for three weeks, while Isabella was on CPAP for two days.

All three were transferred back to Wagga Base at five weeks old and spent a further four weeks in hospital before being discharged at 38 weeks.

The Dunn family are thrilled their only children have overcome the odds to attend KU Kangaroo PreSchool in Wagga.

"It's quite quiet around the house," Mrs Dunn said.

"We're just so proud of them.

"It's another chapter starting."

The family has been supported by L'il Aussie Prems Foundation, which supports families who have given birth prematurely across Australia.

The organisation, which has voted Wagga Base Hospital to be one of the four recipients to receive support this year, will celebrate its fifth year of raising premature birth awareness through its annual Wear Green for Premmies event in April.