Like many twins, they are dressed alike, right down to their pink and white bootees.

But Kendall and Baylee are no ordinary twins. They are one in a million.

An amazing quirk of genetics means that one sister has black skin and the other is white.

(Father Curtis Martin and mother Rebecca Horton cradle twins Kendall (centre left) and Baylee (centre right) who were born with very different skin tones thanks to a rare quirk of genetics)

The effect is so striking that even their own father has said it is hard to believe that they are related.

And their mother, Rebecca Horton, said: ‘When they were born, we kept staring at both of them – we couldn’t believe it.

‘It was a lovely feeling and a big shock.

‘One thing I know for sure is that family and friends won’t ever struggle to tell them apart.’

The little girls’ contrasting looks can be traced back to their parents.

Their father, Curtis Martin, is half-Jamaican, while their mother is white.

As non-identical twins, they were created when two eggs were fertilised by two sperm.

This means they have inherited different genes from their parents.

Normally, you would expect both to inherit a mix of black and white genes and be born with a similar skin tone.

Miss Horton, 28, is white, while Mr Curtis, 24, is half Jamaican. Their twins’ skin contrast is possible because the girls are non-identical, though it is still highly unlikely

But, in odds of a million to one, Baylee has inherited a set of genes for white skin.

And Kendall’s genetic inheritance includes some genes that code for black skin, passed on from her mixed-race father.

The twins also have very different characters.

Kendall, who weighed 6lb 1oz when she was born three months ago, is very laid-back and likes nothing more than to sleep the day away.

In contrast, Baylee, who was slightly heavier at 6lb 5oz , is ‘loud and needy’ and loves attention.

This could come in useful, as she and her sister are already attracting attention wherever they go.

Their mother, a 28-year-old delivery driver for Asda, said: ‘When people look in the pram and see that one is darker than the other, they will sometimes be a bit thrown and ask if they are twins.

‘They are shocked when we say yes.’

Mr Martin, a 24-year-old builder from Kingswinford in the West Midlands, told the Sun: ‘Everybody loves them.

‘We’ve got used to it but you hear people whisper as we walk past.

‘If I saw them out, I don’t think I’d believe they were related.’

The couple, who also have a five-year-old son called Coby, knew from quite early on in the pregnancy that Rebecca was having twins.

However, they weren’t prepared for how much work would be involved.

But while they have completely forgotten what it is like to have a good night’s sleep, they wouldn’t have it any other way.

Allan Pacey, a Sheffield University fertility doctor, said that just as twins can have different hair or eyes, they can also be born with skin of different colours.

And just as a baby’s hair often changes with age, with blonde hair, for instance, darkening, the twins’ skin may yet change.

This could lead to them looking more similar – or even more different.

Professor Pacey said the girls’ contrasting skin colours are caused by the way their parents’ genes were shuffled before being passed on.

He said: ‘This shuffling has created something that is completely unexpected and throws us but it is just nature’s way of making us diverse.’

[via Daily Mail]