When Taylor Swift's longtime best friend, Abigail, celebrated her 25th birthday, the pop star pulled out all the stops to make it a special night. Both Taylor and Abigail took to Instagram to share sweet videos from the fun party, which included a surprise appearance by Chris Carrabba, the lead singer of Dashboard Confessional — Abigail's favourite band. In the clips, the best friends can be seen belting out the song "Hands Down" alongside Chris, with the whole party joining in and singing along. On Instagram, Abigail wrote, "Dude. Still crying. I died. There's no way. @ChrisCarraba sang me a birthday song." She added, "Thank you @taylorswift & all of my incredible friends & family for making my 25th birthday the most magically memorable night I've ever had." Paramore's Hayley Williams and model Lily Aldridge were also at the star-studded bash, and the group sported fun props to snap pictures in a photo booth. Take a look at the best pictures and videos from Taylor's fun night celebrating her BFF, and then peek at the pair's hilarious pictures from the Grammys earlier this year.