Chinese twin sisters who were separated as babies and adopted by two US families before meeting for the first time as ten-year-olds now see each other 'several times a year' and have 'astonishing' similarities, their families have said.
Gracie Rainsberry and Audrey Doering, now aged 13, grew up hundreds of miles apart after being found in two different places and taken to the same orphanage in China.
Audrey grew up nearly 1,500 miles away from her sister in Wausau, Wisconsin, while Gracie lives in Richland, Washington.
Now a new TV show examining long lost families sees the girls travel to London to be tested by experts specializing in identical twins.
The twins visited St Thomas' hospital in central London in April, for the ITV series Long Lost Family to meet expert Professor Tim Spector to conduct tests looking at whether nature or nurture make up their personality and behaviors.
During the trip their bone density, balance, grip, lung capacity and eye sight were tested and compared.
Their new families had no idea the girls had a sibling until they were aged 10, when Audrey's mother, Jennifer Doering, found a photo of both youngsters together as babies, posing with their Chinese foster mom.
The pair were reunited live on air 'Good Morning America' in December 2017 after speaking to each other for the first time via FaceTime.
The two sisters, who both wear glasses, had even arranged to wear identical outfits for their first face-to-face encounter since their separation.
Despite their upbringing in different parts of the country and not regularly seeing each other until the age of 10, the girls' parents say they act and behave similarly.
During their first reunion he twins first found out they both love chicken Alfredo as well as mac 'n' cheese.
They now meet up several times a year, including going to summer camps together, and Audrey went to Gracie's home for Christmas last year.
Audrey said she misses her sister when they are apart and that the only difference between them is their dress sense.
She told the Mirror: 'I just love being together with her. When we're not together I miss her a lot. We speak or text every day. We have this connection, it's like she's part of me.
'The only way we're different is I dress up more than Gracie. I like wearing girly clothes and she wears more sporty clothes.'
Mrs Doering found out her daughter had a sibling when the schoolgirl asked for a sister for Christmas.
Instead Mrs Doering wanted to give her daughter a copy of her 'finding ad', which is an image published in Chinese newspapers when a baby is placed in an orphanage in a bid to find the parents.
She managed to track down a copy of the ad and was shocked to find it included a picture of not just one, but two babies wearing matching outfits.
Mrs Doering said: 'We've been astonished at how alike they are. They talk the same, like the same things, right down to their favorite food and subjects.
'They are laughing one minute and crying the next. They both get nervous a lot too, and when they do they push their glasses up their noses in exactly the same way.'
The Doerings dug further and found that the other baby in the picture had a birth date close to Audrey's and shared her congenital heart condition.
They contacted the Rainsberrys and broke the news to their daughter.
Nicole Rainsberry, Gracie's mother, added: 'It was amazing to me that math was both their favorite subject and despite both having heart conditions that they were amazing athletes.'
Gracie said her sister is like 'another part of me' and that they regularly meet up.
She said: 'I'm not sure how to explain it. Getting to have her is like having another part of me. Whenever we talk and get together, I just feel a connection.
'I can talk to her about a lot of things and I know she will help me through it, and I feel I can do the same for her.'
Describing the moment the pair were reunited in 2017, Mrs Doering she was stunned at the similarities between Gracie and Audrey even in that initial meeting.
She said: 'When both girls came up on the screen it was an incredible moment. They just looked at each other and started crying.
'Both had their hair in ponytails to one side, and were wearing the same pair of glasses.
'Even though we live in different parts of the country, they spoke in exactly the same way. Their mannerisms were exactly the same and they even cried the same way.'
Long Lost Family Twins: What Happened Next, ITV tonight at 9pm (GMT), 5pm (EST) and 2pm (Pacific Time).