WINTHROP — Happy first birthday, Christopher Presti.

It’s been a long time coming — four years to be exact.

Christopher, who goes by the nickname Cru, turns 4 years old today. Because he was born on leap day, Feb. 29, a date which only comes along once every four years, this year will the first time his actual birthdate has been on the calendar.

Cru was born at 7:18 a.m. on Feb. 29, 2008, at Wateville’s Inland Hospital.

The Prestis will have family and a few close friends over for Christopher’s birthday today, but they have bigger things planned for next month.

The whole family, which now includes Cru’s 18-month-old little sister, Meelah, is headed to Disney World in Florida at the end of March, to celebrate Cru’s “first” birthday.

“The trip to Disney is kind of for his first birthday,” said father Chris Presti. “We’ve been showing him lots of Disney stuff. He’s quite excited.”

It’s not that Cru goes without a birthday celebration when it’s not a leap year. His family still has birthday parties every year, throwing them whatever weekend happens to be closest to his Feb. 29 birthday.

Cru’s mom, Heidi, still works in the birthing center at Inland Hospital, where Cru was the hospital’s first-ever leap year baby and the first one reported in central Maine that year. Chris Presti works for his family’s cheese spread business, JP Spreads, in Winthrop.

Leap years, which come every four years, contain 366 days in the common Gregorian calendar, rather than 365 days.

According to the website www.timeanddate.com, leap years were added to the Gregorian calendar in 1582 as a means to keep the calendar correctly synchronized with Earth’s revolutions around the sun, but were first introduced in 45 B.C. by the Greeks.

It takes the Earth approximately 365.242199 days — or 365 days, 5 hours, 48 minutes, and 46 seconds — to circle once around the sun. However, the Gregorian calendar has only 365 days in a year, so if a day weren’t added nearly every four years, almost six hours would be lost off the calendar every year. After only 100 years, the calendar would be off by approximately 24 days.

It can be a strange concept to wrap your mind around — this date that only comes once every four years. Especially if you’re just 4 years old.

Asked by his grandmother if he knew what day his birthday was, Cru said it was on grasshopper day, his father said.

Not much of a leap to see where that came from.

Keith Edwards — 621-5647

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