Blake Lively and Ryan Reynolds Credit:

Sisterly love! 

Blake Lively returned the favor to her Sisterhood of the Traveling Pants costar Amber Tamblyn by attending her wedding on Saturday, Oct. 6.

Tamblyn, 29, tied the knot with Arrested Development actor David Cross, 48, in a non-traditional outdoor ceremony. The bride wore a canary yellow dress and walked barefoot after arriving to her ceremony by canoe.

Lively, 25, and her new husband, Ryan Reynolds, 35, were guests at the beautiful fall wedding. The couple were photographed at the ceremony dressed casually in blazers. On Sept. 9, Tamblyn attended Lively's wedding to Reynolds at Boone Hall Plantation & Garden in Mount Pleasant, South Carolina with Traveling Pants costars America Ferrera, 28, and Alexis Bledel, 30.

The Sisterhood women have remained close since starring together in 2005's The Sisterhood of the Traveling Pants and 2008's The Sisterhood of the Traveling Pants 2, and all reunited again to celebrate Tamblyn's big day. Ferrera, who married Ryan Piers Williams in June 2011, was photographed sharing some laughs with Amy Poehler -- who recently separated from Cross' Arrested Development costar Will Arnett after 9 years of marriage.

Yo La Tengo performed during the reception and Questlove acted as deejay. "We played Superchunk ('Driveway to Driveway'), Pixies ('Here Comes Your Man'), and Mission of Burma ('Academy Fight Song'). Also ZZ Top's 'Give Me All Your Lovin',' Replacements' 'Kiss Me on the Bus,' Altered Images' 'See Those Eyes,' plus a few of our songs, all at the request of the bride and groom," the band told Us Weekly. "A couple of others that we thought would fit the occasion."