The "Me Too" singer spoke to ET's Brendon Geoffrion after performing at CBS Radio's 4th Annual We Can Survive Concert at the Hollywood Bowl on Saturday, revealing how she met her beau.
"Chloe Grace Moretz told me she had a really, really nice friend. I was like, 'That’s crazy! I'm looking for a really, really nice guy,'" she recalled. "And she's like, 'You guys have to meet.' And we did. He’s great!"
Trainor gushed about their trip to the Spanish capital, where she played a number of shows, sharing that the romantic journey was "pretty special."
Sabara has been on the road with Trainor during her Untouchable Tour, and the 22-year-old singer marveled how they've "traveled the world together already in just a short amount of time."
"Working with Michael is incredible. He’s one of the nicest [people] I've ever met," she explained. "He called me, and I was on a shoot, and he was like, 'I would love you to sing with me." And I was like, 'That's only a dream of mine!'"
"I've listened to him forever and to have him say that was incredible," she added.
As for performing at the star-studded We Can Survive concert, Trainor was "honored" to be invited to participate, telling ET, “This is kind of a new [charity concert] but still a huge deal. Only huge artists on the previous shows that I love have been here. So to ask me, I was like, ‘OK, I'll do it. Yes.’"
The event, which was held in honor of National Breast Cancer awareness month, also hit close to home for Trainor, who shared that two of her close childhood friends lost their mothers to breast cancer when they were kids.
"It's so important to be here today, and I hope they are watching out there," Trainor said.