All the details from J.Lo and A-Rod's engagement! How he proposed! Plus, how does her new rock compare to past rings! But why is one celeb accusing A-Rod of cheating? Plus, what Katherine Schwarzenegger is only telling ET about her wedding to Chris Pratt! Then, Justin Bieber's cry for help. Why he's asking fans for prayers. And, Luke Perry's fiance speaks out for the first time. Her surprising revelation about their relationship. Then, Olivia Newton John comes to the ET stage. What she wants fans to know about her stage four cancer battle.