Ross and Emily played two songs when they got married.

When the best man and bridesmaid entered, they played "Tired Old Souls" played by Scottish bagpipes.

When the bride Emily entered the venue, the familiar wedding march "Here Comes the Bride" was played, also played by Scottish bagpipes.

I think you are talking about the first song. Here is the link to the first song "Tired Old Souls"/search/trk/Tired20Old20Souls

Hope it can help you.