In Daughters of the Bamboo Grove, the journalist profiles twins separated as toddlers by China’s one-child policy and examines America’s demand for international adoptees.

How brutally was China’s one-child policy enforced?

The Family Planning agency was really scary. They levied fines of five, six, seven times annual income, depending on how many kids you’d had. They vandalized violators’ houses. They hauled parents in for forced abortions and sterilizations. And they stole children.

Your book follows identical twin girls, Fang and Shuangjie, who were separated. What happened?

When the girls were toddlers, their parents left Fang in their village with relatives and took Shuangjie with them while they did migrant work. They separated the twins so that they wouldn’t be so noticeable. But Family Planning noticed Fang. Her relatives managed to hide her a few times, but she was eventually caught. She was kidnapped by Family Planning and they handed her over to an orphanage. She was quickly adopted; the orphanage forged documents claiming she was abandoned.

Was there a profit motive?

Orphanages got a “donation” from adoptive families, so there was a big incentive to get kids. It became a supply chain problem. Most of the abductions started in 2000, when there was a huge demand in the U.S. for baby girls from China, who were considered the perfect adoptees, just as China was getting wealthier and parents weren’t abandoning girls anymore. So, the supply crashed while demand was soaring.

You helped reunite Fang, whose American parents named her Esther, with her Chinese family. How did you track her down?

I was pretty sure Fang was taken to an orphanage that had a social media group associated with it, where American parents posted pictures of their adopted daughters. So, I made a lineup that included Esther’s photos from the group and sent it to Fang’s parents. They picked her out immediately.

You took 18-year-old Esther to China to meet Shuangjie. What was that like?

American kids are taught that you can be anything you want; Esther had that confidence, Shuangjie didn’t. But there were obvious similarities. They’re both very artistic: Esther’s a photographer; Shuangjie does calligraphy. Their personalities are both very disciplined. They have similar styles of dress. Studies say that identical twins raised apart become more alike as they get older: core personality traits come out the farther away you get from whatever was stamped on you. It seems like they are growing more alike, although their lives are quite different.