User blog comment:FairyRaven/Fairy Tail Chapter 467: Mother's Key, Review and Commentary/@comment-1359322-20160104115124/@comment-5303512-20160105005047

Another thing that makes my theory that the Spriggan 12 Jacob is responsible for Marin's sudden attack might also play into the whole story with Layla and Grammy. He might be the cause of Brandish joining Alvarez and why he had Marin try to kill her to silence her.