Leap Year: What it's like being born on 29 February?
Imagine only having a birthday every four years.
On 29 February, about 5 million people around the world celebrate their once-every-four-years 'real' birthday.
For some of the so-called 'leaplings,' being born on 29 February is an excuse to celebrate over two days when it's not a leap year - but for others, getting into nightclubs is tricky when the bouncers think their security is fake.
The BBC spoke to leaplings all around the world.
Produced by Tiffany Wertheimer, voiced by Mattea Bubalo, edited by Susie Smith and Lorna Acquah