Taylor Swift surprised and made a couple's engagement even sweeter.

The "Love Story" singer helped one of her biggest fans surprise his boyfriend after he proposed to him this weekend. Alex Goldschmidt, whose been a longtime Swift fan and friend of the singer's, took to Instagram on Saturday to share a snap of him and his fiance, Ross, beaming as they posed with Swift at Sycamore Tavern in Los Angeles. In the pic, the blonde beauty wears a blue floral dress, dons red lip stick and has her hair in a ponytail.According to Swift, Goldschmidt had emailed her and told her about his plans to propose. He also mentioned her hit "King of My Heart" was a special one for the duo. So, Swift agreed to attend their engagement party at the Sycamore Tavern in Los Angeles and surprise Goldschmidt's fiancé with a sweet serenade.

Of course, the couple's family and friends were completely shocked to see the 10-time Grammy winner walk out with her guitar.

"I've been off tour for a while, but hopefully it's still all right," she said before performing the number. twitter Alex Goldschmidt                                                                                                     
‏Verified account

What a sweet way to celebrate such a joyous moment. Not everyone can get in touch with Taylor freaking Swift, but this just goes to show: it never hurts to ask! Based on Goldschmidt's Twitter feed, Swift stuck around for at least a little while after her performance to chat with the happy couple and pose for a few pics                                                                                                      

 twitter Alex Goldschmidt