WITH record-breaking birthdays year after year it was only fitting that Jane Gray was treated like royalty at her 112th birthday celebration today.

The Smithfield resident, who is Australia's oldest person, was surrounded by family and friends at her nursing home for the party.

Mrs Gray is quite familiar to the fuss but for grandson Andrew Betts "Nan is just Nan".

"Her age doesn't mean anything to me, she's just Nan," Mr Betts said.

"She's a rock and she has always been here. I forget that people don't see anyone this old but to me she's just my Nan. She's an amazing lady."

Mr Betts visits his grandmother at SummitCare Smithfield on a daily basis after she moved into the aged care home in March this year.

"It was disappointing because it wasn't the plan. It got to a point when I was at mum's every weekend so mum could go out and have a break," he said.

"She still eats well, she pours salt on her food like snow but dementia has now got her."

During a prayer before her birthday celebration lunch today, Mrs Gray said: "I hope they hurry up because I'm dying to get stuck into this doughnut."

SummitCare Smithfield operations manager Leona Calpito said Mrs Gray always kept the staff entertained with her humour.

"She has a very, very dry sense of humour. We just feel really honoured that we have her here and that's she's happy with the care," Ms Calpito said.

"She is an inspiration and she is still doing very, very well."

Assistant in nursing Yvonne Honour added: "She still has her facilities so she knows what she wants and she knows how to get it."

Mrs Honour has worked in the industry for 17 years but has never come across a character like Mrs Gray.

"She's one of those people you will remember long after. She is an archive, a living archive. We are proud to be in her presence," she said.

On Sunday, daughter Heather McKenzie and family visited Mrs Gray to celebrate her birthday.

"All my children came up in dribs and drabs over the day so I brought a cake and she blew the candles out. It was a lovely day," Mrs McKenzie said.

Mrs Gray was born in Scotland on December 1, 1901, and migrated to Australia with her husband in 1927.

At age 112, the super-centenarian is currently ranked as the 35th oldest person in the world.