Up until today, I thought I knew just about everything there was to know about twins.
Firstly, because I am a twin. And secondly, because I have twin brothers. We have a twin club and no-one else is invited. Not even mum and dad.
I know that as a kid being called “twinny” made me want to punch grown adults in the throat.
I know what it’s like to be pinched on the arm before someone laughs so loud a little bit of spittle gets in your eye, and they exclaim, “DID YOUR TWIN FEEL THAT?”
No. No they didn’t.
I know how embarrassing it is to walk past a mirrored corridor at uni and say, “Hey Clare, I didn’t know you were at uni today!” before slowly realising she most definitely is not.
I know what it's like to have someone excitedly tell you, "No you're identical! You're definitely identical!" when identical isn't, like, a matter of opinion. It's about an egg. And guess who wasn't there 26 years ago when that egg split, huh? You. You weren't there.
I thought I knew all the things - and so did the Burgess brothers.
They are, second to my siblings and I, perhaps the most iconic sporting families in the country.
The eldest of the four, Luke Burgess, currently plays professional Rugby League in France, while twins Tom and George play alongside their older brother, Sam Burgess, for the South Sydney Rabbitohs.
As Sam, Tom and George were grilled by comedian Katie Burch for Who's in The Car, Australia's version of Carpool Karaoke minus the singing (thank God), Katie explained that her husband is also a twin. But he's not your average twin. He out-twins us all.
Her mother-in-law fell pregnant, while she was already pregnant.
My mum talks about how she had two sets of twins in two and a half years. Post continues below.