Although she knew she was adopted from about the age of seven, the older sister, Sun Ye, did not know she had a twin sister until she was 21.

She began searching, and a decade later, an old neighbour of the younger sister, Liu Yan, sent Sun a link to her Douyin account, saying they look exactly the same.

Sun immediately knew it was her sister. She said she and her cousin from her adoptive family looked through 300 videos on Liu’s account and managed to locate her from the details in her videos.

They went to Liu’s workplace but were told she had resigned. They begged a former colleague to give them the phone number of Liu’s best friend after failing to establish direct contact, and they sent photos to show her Liu has a twin sister.

Liu had not known she was adopted and thought Sun was a scammer who had photoshopped her face onto another person’s body. Liu’s aunt later confirmed she was adopted and has a twin.

The sisters, who live 90 minutes driving distance from each other, met for the first time in March 2022.

Sun said that when they first met, she was stunned to see a person identical to her standing right in front of her.

To their surprise, the sisters also have the same voice, choice of hairstyle and taste in clothes, and have called their sons by the same English name, Kevin.

They said they immediately connected and took each other to their adoptive homes, and feel they now have a double family. They also tracked down their birth parents.

It is unknown why their parents chose to have their twin daughters adopted, but some online observers said that was common for families who had many children and could not afford to keep them all.

As for how they are sure who the elder sister is, Sun said her father knew he had adopted the twin.

They said they are cherishing every “first moment” they have together after the reunion.

They have opened two women’s clothing shops, which had been Liu’s dream before she met Sun.

They are also having some fun with their identical looks, playing pranks with their husbands and sons, and unlocking each other’s phones with facial recognition.

“How nice it would have been if we could have grown up together, but I hope we spend the rest of our lives happily from now on,” Sun said.

Their story has amazed many people online.

“They are so lucky to have found each other finally,” one person said on Douyin.

“They are destined to be together, no matter how long they have been apart,” another said.