Amy Smart and Carter Oosterhouse smiled for cameras outside of their NYC hotel Thursday. The duo announced their engagement last week and Amy Smart showed off her gorgeous diamond ring at an event on Thursday. The appearance was in support of The Body Shop's three-minute shower challenge to promote water conservation. Amy and Carter have a shared interest in eco-activism, and the couple apparently celebrated Earth Day on Friday by bathing together. Carter also observed the holiday by sharing green tips and outdoor design ideas on The Today Show as an extension of his weekly HGTV show, Carter Can. Amy also has a place on the small screen in Showtime's Shameless, which was recently renewed for a second season.