"It's going to be hard for me to do this next song. I'm not sounding like myself, and I'm not feeling like myself," the pop star, 21, told the crowd as tears streamed down her face during a sound check. "I'm sure you guys already know the reason I'm upset. My dog … I shouldn't say he was my favorite, but he was my favorite. He passed away."
She then dedicated Fleetwood Mac's "Landslide" to Floyd, her Alaskan Klee Kai. "I just want to do a song for him because we used to always listen to Fleetwood Mac together, and it was his favorite song," she said.
Cyrus had to stop singing to cry several times during the sound check, attended by thousands of fans who didn't get to see the pop star in Boston in December when a snowstorm halted her travel plans and forced her to cancel a concert appearance.
She also broke down while singing Lana Del Rey's "Summertime Sadness" and Coldplay's "The Scientist" in honor of Floyd. During "The Scientist," her little sister Noah came out on stage and gave her a hug.
During the concert later that night, a teary-eyed Cyrus asked fans for emotional support. "Your responsibility is to get me through, I think, the hardest day of my entire life," she said, to raucous cheers.
"She held it together, but talked about it three or four times," said one concertgoer. "You could see tears."