Reese Witherspoon Cameron DiazCr Donato Sardella/WireImage

Reese Witherspoon made her first official appearance since giving birth just one month ago to her third child Tennesse James when she toasted to the opening of the Los Angeles flagship of Rag & Bone this weekend with pal Cameron Diaz. The two actresses (clad in head-to-toe Rag & Bone) sipped on bubbly and shopped duds from the brand, whose new 9,000 square-foot, two-floor art deco-inspired store marks its first-ever West Coast location. Click through the gallery to see more photos from this weekend’s biggest parties.