This weekend, actress Amber Tamblyn tied the knot with her Arrested Development actor fiancé David Cross, but the couple’s small, rustic ceremony was witnessed by some of the industry’s biggest stars. Not only did hilarious actress Amy Poehler and actor Jason Ritter witness the nuptials, but all of Amber’s Sisterhood of the Traveling Pants co-stars were also in attendance to see the bride and groom say "I do." America Ferrera looked happy for the couple, posing with Amy for cheeky snapshots that were later shared with the Twitterverse, and Gilmore Girls star Alexis Bledel was also there to congratulate the newlyweds. Blake Lively attended with a plus one, her new husband, Ryan Reynolds, who looked sincerely happy for the new couple in a Twitter photo of the two guests at the ceremony. The Roots musician, Questlove, was the pair’s DJ for their big day, and Yo La Tengo did the honors of playing live at the reception. Talk about a star-studded guest list!