Megan, 24, says that her twin sister, Mandi’s, extreme competitiveness is destroying their relationship. Megan says that Mandi puts her down and brags that she is the “better” twin — because she has more money, a cuter husband and a nicer house, among other things. Mandi admits that she likes feeling superior to her sister and chalks up her antagonism to normal sibling rivalry — but does her behavior cross a line? Dr. Phil gets to the root of Mandi’s need to compete and compare. Is she open to making a change? Then, Paula says her 19-year-old identical triplets, Christina, Brianne and Ashley, have gone from best friends to biggest enemies because of their competitiveness, and she fears the sisters will be forever divided if something doesn’t change. Can they learn to stop the petty rivalry and come together as a family? Plus, Noel says that she’s struggled with depression for years, and it’s taking a toll on her marriage to her husband, Don. He says he wishes Noel would “snap out of it