The story about the baby born with a brain tumor containing a tiny foot inside has gone international, but the family has stopped talking to the press because 20/20 will have the exclusive in January, according to 7News (warning: yucky video and pictures ahead.)

Dr. Paul Grabb operated on Sam Esquibel at Memorial Hospital for Children after an MRI showed a nearly perfect foot and a partial foot, hand, and thigh, according to The Associated Press (via The New York Daily News).

Grabb called the growth “borderline unheard of” and doesn’t know what caused it. One theory is that it was a highly unusual case of “fetus in fetu,” in which a fetal twin begins to form within the other. Another is that the growth could be a congenital brain tumor composed of foreign tissue, according to 7News.