Here comes the bride! After accepting a proposal from boyfriend William Tell, Lauren Conrad took to Instagram on Oct. 13 to share a photo of her round-cut diamond engagement ring. "Best surprise ever," she captioned the shot. Later that day, on her blog, the former Hills star wrote, "I am very excited to share with you guys that William and I got engaged over the weekend. I am beyond thrilled! Get ready for lots more wedding content here on LaurenConrad.com as we begin the planning process."