Passers-by might have been forgiven for taking a second, or even third look at Blenheim Palace as it hosted Britain's largest gathering of multiple-birth children.
More than 1,500 thousand twins attended the record-breaking party
In attendance at the party on Saturday were 577 sets of twins, 52 sets of triplets and a family of quads.
The get-together has been organised by Tamba, a charity which supports multiple-birth families, to celebrate its 25th anniversary and the launch of its new helpline.
A communal picnic on the lawns of the Oxfordshire stately home started at lunchtime, when party-goers cut a giant birthday cake.
It's double the laughs, double the joy and you are doubly blessed
Linda Jones, mother of twins
Children were also invited to bring along their favourite teddy or doll for a best-dressed competition.
Tamba's Rachael Hodgetts, who has twin sons, said: "There are a lot of issues that put pressure on the parents of multiple birth children.
"Feeding singleton children can be hard, but you just can't do two, three or even more children all at the same time, for example."
But Linda Jones, mother of four-year-old twins Emily and Melissa, said having twins could also be twice as nice.
"People often stop you in the supermarket and say oh, double the trouble.
"It is, but it's also great, it's double the laughs, double the joy and you are doubly blessed."