Mary Drake on Pretty Little Liars (SPOILER ALERT) said a few weeks ago that in addition to Charlotte DiLaurentis, Spencer is also her daughter. But the surprises aren't over yet. There's a fan theory circulating on Tumblr that Mary could have a third child.The Tumblr thebestplltheories is confident that Bethany is Mary's daughter. Their reasoning? "How the hell did it happen that the police mistakenly identified Bethany’s body, to be Alison?" they wrote. "Alison never died, and somehow they thought it was her in the grave, when really it was Bethany. The ONLY explanation for how this happened is that Alison and Bethany have similar DNA."This would also explain, according to the post, why Jessica DiLaurentis wanted Bethany to call her Aunt Jessie. Because she is literally her aunt.The puzzle pieces do seem to fit together. And in the complicated realm of Pretty Little Liars relationships, another unexpected connection between characters would certainly not be out of the ordinary.