Woah.

The 42-year-old mother of the boy, who is not named in the study, began trying to get pregnant using IVF ten years ago. At the time, she and her husband received embryos from a heterosexual couple who had themselves undergone IVF.

That couple had anonymously donated their leftover embryos after the woman successfully gave birth. Thing was, they did so in 1990 – meaning that the boy just born to the woman in the study has a sibling out there somewhere who was conceived at the same time but is 20 years younger.

via Baby Born From 20-Year-Old Frozen Embryo.