Most people have birthdays every year but "leaplings" have them only once every four years, which is why Lucy Snelgar is celebrating her 21st.
Not bad for a woman who turns 84 today.
Miss Snelgar, who has lived in Rotorua for many years, has been the guest of honour at celebrations put on by a brood of nieces and nephews in her childhood hometown, Whangarei.
Sixty-three years ago, the first time Miss Snelgar had a 21st birthday, she was "too shy" to want to be the centre of attention. Besides, she said graciously, her parents had raised a large clutch of children and she didn't want to tax their resources. As was more usual than a big party in those days, the day was marked with a formal studio photograph of the birthday girl.
With the 29th only turning up every four years, her family always celebrated her birthday on February 28 - even in Leap Years.
"Mum and Dad made my birthday the 28th so I could have a celebration like all the other children did on their birthdays every year," she said.
She has never heard the expression "leaplings" before, "but I always knew I was a Leap Day baby, and I felt very privileged to have something so special."
When Miss Snelgar was really 21, she threw herself into sport - roller-skate dancing, marching, netball (called basketball back then), swimming and cycling. Outside of sports, fun was also had at Saturday night dances.
After "a broken romance" Miss Snelgar threw herself into putting it behind her, taking buses to various towns and locations around New Zealand and then sightseeing on her cycle. "I rode my bike all the way from Hastings to the gannet colony at the end of Cape Kidnappers once," she chuckled.
She smiled at the suggestion she could at any time have proposed to some lucky fellow on Leap Day - an old tradition that holds it's the one day women can pop the question.
She then told the story of a beautiful romance, and her broken heart.
"In my early 30s I had a gentleman companion, a very dear friend," she shared. "We went into the motel business together and then the house renovation business."
Over time, the couple moved from friendship to romance and became engaged, but the love of her life died suddenly before they could be married. Miss Snelgar still lives in Rotorua where they were together, but the pull to family and her old hometown is strong. Fit and well at 84 - although not quite feeling a quarter of her age - "Aunty Lu" visits Whangarei several times a year. She describes those visits north as "a joy".
Looking back over a lifetime of her elusive birth date, and sitting in her niece's home which is festooned with 21st birthday decorations and the symbolic key to the door, Miss Snelgar declared this birthday has been the best ever.
Leap Day, or February 29, keeps the long-term calendar in sync with the seasonal or solar year because the earth doesn't orbit the moon precisely in 365 days. Without the one-day four-yearly adjustment, the annual calendar would eventually drift from the astronomical and seasonal events it is meant to track. The Egyptians figured out the need for an extra day to keep things in kilter, their solution adopted by the Romans who designated February 29 every four years, that date retained in the later Gregorian calendar. Years with 365 days are known as common years.
The Olympic Games and the US presidential elections are always held in Leap Years.
New Zealand "leaplings" include former Governor General David Beattie (born 1924) and composer Gareth Farr (1968). Leaplings through history include Pope Paul III (born 1468), Italian composer Rossini (1792), US entertainer Dinah Shaw (1916), and a Norwegian chap, Lief-Martin Henriksen (1968) who was the third sibling to be born on three consecutive Leap Days.