John Medina/Getty Images

Watch The Most Intimate Moment Of Taylor Swift’s 1989 Tour To Date

Tay sang 'Ronan' for the second time ever, honoring a young boy who passed away from cancer.

By now, Taylor Swift fans know pretty well what to expect from the 1989 World Tour. We’ve given you a track-by-track breakdown of Tay’s set list and a review of all the amazing glittery outfits she rocks onstage. And, of course, everyone knows to look out for a famous face or two when Taylor performs “Style.”

But during her show in Glendale, Ariz., on Monday night (Aug. 17), Taylor did something she’d never done on her 1989 Tour before — or any of her other tours, for that matter — when she performed “Ronan,” a song she’s only sung live once before.

Taylor wrote the song for Ronan Thompson, a boy who died from neuroblastoma in 2011 at the age of four. She performed it for the first (and, up until last night, only) time in 2012 at Stand Up for Cancer, and included it in her Glendale setlist because Ronan’s mother, Maya Thompson, was at the show.

Before diving into the emotional ballad, Taylor gave a heartfelt introduction during which she talked about how she wrote the song based on blog entries written by Maya. Holding back tears, Tay also mentioned that cancer recently hit close to home for her after her mother, Andrea, was diagnosed in April.

Maya posted an Instagram video of Taylor’s introduction, thanking her in the caption for remembering her son. “I still can't believe tonight. I still can't believe you did this. This will forever be one of the most special moments of my life. Thank you @taylorswift for your beautiful heart and for never forgetting my Ro. I love you to the moon and back,” she wrote.

Maya also posted a sweet snap of her family meeting up with Taylor backstage, which she fondly captioned, “I love you. @taylorswift You have my heart for the rest of my life and beyond.”