Over the weekend, the mother-of-two stepped out to attend the nuptials looking positively gorgeous. Lively wore all black for the occasion and posted a sweet picture with her friend on Instagram.
"Most beautiful bride on the planet," the actress wrote. "And the best friend I could ask for."
The 29-year-old also made sure to highlight details on the wedding gown, as only a true friend would.
Though not much is known about the pair's friendship, Lively appeared on her friend's Instagram timeline in a photo from the Met Gala earlier this year.
Just last week, Lively and her husband, Ryan Reynolds, welcomed their second child together; the couple also has a 22-month-old daughter named James. Notoriously private, the actors have yet to share any details on their new little one, including the baby's name or date of birth.