Five years ago, Jean-Sebastien Hertsens Zune went looking for his parents. He already had one set, a Belgian church organist and his wife, who adopted him as a baby from Guatemala and later moved the family to France. But he wanted to find his birth mother and father. When Zune was a teenager, his Belgian parents gave him his adoption file, holding back only receipts showing how much the process had cost. Most people pay little attention to their birth certificates, but for adoptees, these documents, along with notes about their relinquishment, tell an often patchy origin story.