In 2007, 3-year-old Madeleine McCann vanished from her bed during a family vacation in Portugal. Her parents, Gerry and Kate, say they dined with friends at a restaurant about 60 yards away from their holiday apartment and checked on the children regularly throughout the evening when Kate discovered Madeleine missing at around 10 p.m.
 
It has been 16 years, and there have been many theories as to what happened to Madeleine. Watch the video above to get caught up.
 
Recently, 21-year-old Julia Wendell of Poland captured the attention of millions across the globe when she said she believes she may be Madeleine. However, Wendell’s parents in Poland deny she is Madeleine McCann and insist she is their biological child. On Monday’s episode of Dr. Phil, "Exclusive: 'I Believe I am Madeleine McCann,'" in an exclusive interview, Wendell shares what she claims is evidence that makes her believe she is Madeleine. Check local listings to see where you can watch.