Patty Hensel remembers the day her twins, Abby and Brittany, were born.

“I went into hospital thinking I was going to have one baby,” she said. But instead, Patty gave birth to a very rare, special set of twins; her daughters, Abby and Brittany.

The babies were conjoined, sharing a body, with two separate necks and heads.

The doctors immediately suggested a separation, but knowing that would mean one girl would die, Patty and her husband Mike refused.

“To me, they were beautiful,” Patty said.

Watch: What’s life like as a twin? Post continues after video.

The Minnesota family took the girls home to their quiet farm, allowing them to be raised away from public scrutiny, and ensuring they had the space to achieve whatever they wanted.

Fast forward 27 years, and the twins are university-educated, can drive a car, and are now teachers; defying all medical expectations. Their journey to get to this point in their lives is extraordinary, and proof that determination can make dreams come true.

 

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How Abby and Brittany made history at their birth.

Conjoined twins are very rare, with their prevalence estimated to be 1 in 50,000 to 1 in 100,000 births. Between 40 and 60 per cent are still born and 35 per cent survive for only one day.

Brittany and Abby are known as dicephalus twins, meaning they share a torso, and one set of limbs, but have individual heads and brains – making them two individuals in one body.

The twins also have their own hearts, gallbladders and stomachs.

They do however only have three lungs between them, one liver, intestines, a set of kidneys, pelvis, ovaries, uterus and bladder.

Although their shared body now has two legs and two arms, the twins were born with three arms. This third arm was identified as being a hindrance to their overall movement, so when Brittany and Abby were young, it was removed.

How do Brittany and Abby operate one body?

After 27 years of functioning in one body, the twins’ doctors still have little understanding of how two brains, which control one side of the body each, can co-ordinate themselves to do the actions and activities the twins can: write, get dressed, ride a bike, type on a keyboard, play the piano, and drive a car – or even simply walk – seamlessly.

But whatever the neurological explanation is, Brittany and Abby can function in their body with limited hindrance and astonishing accomplishment.

Their mother admits that sleeping is often uncomfortable for them, but apart from that, their innate ‘teamwork’ means they are incredibly co-ordinated.

But make no mistake: Brittany and Abby are individuals.

For example, Brittany has often had a cold, and even had pneumonia, twice – but Abby hasn’t suffered the same issues.

In fact, Abby complains it’s “boring” being with her sister when she’s recovering from an illness in bed.

The girls eat and drink separately, and have different tastes, but admit it’s easier to eat with utensils and have co-ordinated arm movements if they eat at the same time.

Brittany and Abby’s height difference.

At 158 cm, Abby, who is on the right, is taller than her sister, who is only 148 cm.

The difference in the twins’ height has created an issue for their clothes and shoes, which usually need to be adjusted.

It’s also meant that Abby is inclined to walk with the flats of her feet, whilst Brittany walks on her toes.

To address the height issue, at 12, when it was discovered that Brittany had stopped growing, surgery was performed to hinder Abby’s growth.

Both twins have also had operations for scoliosis.

How Brittany and Abby were educated individually.

Just as they were recognised at home for their separate identities and personal tastes, at school, the twins were treated as two unique students, with different interests and abilities.

School was important to them, because college was always the aim, with Abby interested in maths, and Brittany in English studies.

Both twins sat entrance exams and were accepted into Bethel University, where they came to a compromise: they’d follow their shared passion for education and become teachers.

Abby and Brittany graduated with two separate degrees in education in 2012 and immediately began searching for employment.

How the twins learnt to drive.

Brittany and Abby are by law recognised as individuals, with their own passports and birth certificates. So, it followed that they also needed to have separate drivers’ licenses.

The sisters learnt how to drive together, with their driving instructor acknowledging it was a feat of co-ordination, with him not knowing which set of eyes was seeing the road and sending messages to the brain to steer the vehicle.

On their 16th birthday, the twins took two written tests before they both got their own driving license.

Brittany and Abby’s teaching careers.

The twins are currently working in their dream job as grade five teachers.

However, even though they are two different people, they are only recognised as one – and so earn only one salary, which is something that bothers them.

“As experience comes in we’d like to negotiate a little bit,” Brittany says.

“We have two degrees, and we are able to give two different perspectives or teach in two different ways.

“One can be teaching and one can be monitoring and answering questions. So in that sense, we can do more than one person.”

Public interest in the twins.

The sisters first attracted national public attention in 1996 when they appeared on The Oprah Winfrey Show, at six years old.

After that, they appeared in magazines such as Time, and as the cover story of Life, where their photo was captioned as "One Body, Two Souls".

In 2012 the twins launched their own reality show, Abby & Brittany, on the TLC channel, which focused on their graduation, job search, and the time they spent travelling in Europe; ordinary activities for two extraordinary young women.