An Irish woman is the latest woman to discover she has a doppelganger who looks so like her her own father struggled to tell them apart.

Shannon Lonergan, 21, from County Kerry, Ireland, discovered her lookalike online on the website Twin Strangers after being contacted by Sara Nordstrom, 17, from Sweden.

The pair both share the same blonde hair and facial features which Shannon said 'frightened' her when she met Sara, and even her father did a double take at how similar Sara looked when they met up in Dublin.

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Shannon Lonergan, from County Kerry, Ireland, discovered her doppelganger online on the website Twin Strangers after being contacted by Sara Nordstrom, from Sweden and the pair met in Dublin

Both women look incredibly similar and noticed they had the same lips and pout and even next to each other there is a very strong resemblance

Shannon says she felt 'sick' before she met her for the first time and it wasn't just their looks which were so similar.

Shannon said: 'When I opened the door and saw Sara standing there, literally my heart jumped into my mouth.

'Once I saw Sara’s face I felt my butterflies disappear.

'We had the exact same expressions, pout, smile. It's so weird.'

Shannon, a business student, had signed up to the Twin Strangers site over the summer and after checking regularly for her doppelganger, she had not looked at the site in a while.

Sara joined the site last month and after a couple of searches, she came across Shannon.

The pair then arranged to meet up in Dublin with Sara flying from Orebro, Sweden, where she goes to boarding school.

Sara, left, matched with Shannon, right, on the Twin Strangers site and arranged to meet to see if they were as similar in person

Shannon felt 'sick' before she met her for the first time and it wasn't just their looks which were so similar and she was overwhelmed when she saw Sara

Sara joined the site last month and after a couple of searches, she came across Shannon and though they looked near identical in pictures they were concerned they wouldn't in real life

Sara said: 'I was nervous but very excited before flying to Ireland.

'I was afraid Shannon and I wouldn't look like each other in person but it turned out I had nothing to worry about. She is definitely my doppelganger.'

'It felt a bit surreal when we finally met, a bit like looking at yourself.'

After spending time together in Dublin at the city's Christmas market and and going shopping together, they also found they had a lot of similar interests.

Sara said: 'We’ve both competed at high levels in sport.

'I used to be in the top groupings for show jumping in Sweden and Shannon has placed very highly for dancing in both Ireland and the UK.

'We also seem to see things the same way. There was a bathroom underneath the stairs in the house where we were staying and ­ at different times ­we both commented: “It's just like in Harry Potter".

When Shannon, left, and Sara, right, met each other for the first time they were both surprised and kept looking at each other's faces

The pair hugged when they met and quickly found lots to bond over. Although Sara was shyer than Shannon, it wasn't long before they acted like they had known each other for years

'That was a bit strange.'

Shannon said although their personalities are slightly different, after spending time together they felt like old friends.

She said: 'Our personalities are a little different. Sara was a little more shy, but before too long we talked and acted like we had known each other for years.

Nothing else was different. You bond very quickly with someone who has your face.'

And even Shannon's family, who came along to meet Sara, struggled to spot the difference.

She said: 'When my dad first saw myself and Sara he did not know where to look. He kept looking at her than me and looked so confused.

Shannon, who is also a makeup artist, curled Sara's head and with makeup and the same hair, the pair look identical

Spending the day at Dublin Christmas market, the pair dressed in matching outfits were asked if they were twins by a stranger

'His facial expressions were hilarious and showed how shocked he was. He honestly needed a moment to see who was who.'

Sara had shown her aunt Shannon's photograph before they met and also thought they looked 'incredibly alike.'

Twin Strangers, who released the video of the two meeting, is based on the idea that everyone in the world has seven 'doppelgangers' who look identical to them.

Shannon said: 'I think everyone dreams about meeting their twin, but not everyone knows how to.

'When I signed up I actually never thought I would find my doppelganger but I did.

Uncanny: Niamh Geaney previously found her 'twin stranger' in Karen Branigan (right), through a social media campaign she launched with friends

'I can't stop wondering where my other Twin Strangers are.'

The pair have added each other on social media and plan to stay in touch, Sara said: 'Shannon is the best present I could have asked for.'

The Twin Strangers site has matched up many people with their doppelgangers.

Niamh Geaney, 26, founded the site with friends when they set themselves the challenge of findign their doppelgangers.

After first meeting lookalike Karen Branigan - and staging a photoshoot that went viral - Niamh Geaney from Dublin, Ireland, was determined to track down her six remaining doppelgängers.

Just weeks later, the 26-year-old student and TV presenter found her second lookalike, Luisa Guizzardi - but a little bit further away from home in Italy.