Kelly Clarkson faced an emotional moment during The Voice Knockouts.

On Monday night (October 25), Team Kelly’s Holly Forbes and Girl Named Tom went head-to-head. Forbes delivered a powerful rendition of “Superstar” by The Carpenters, while the sibling group performed their perfectly-blended spin on “Wichita Lineman” by Glen Campbell.

Girl Named Tom’s song selection served as a tribute to their father as he battles terminal cancer. Entertainment Tonight notes that the siblings explained to Clarkson during rehearsals that their father “has such a positive attitude going into every doctor's appointment…It's been huge for us to see that.” The heartfelt dedication was one that tugged at Clarkson’s heartstrings, as the American Idol alum wiped tears from her eyes.

Following the powerful Knockout round between Forbes and Girl Named Tom, Clarkson was at a loss: “What do I do?!” Ultimately, the “Christmas Isn’t Canceled (Just You)” artist opted for Girl Named Tom, and Forbes was saved by another team (both John Legend and newcomer Ariana Grande were vying to get Forbes on their teams). Clarkson explained: “They sound amazing together but then they showed how each of them sound alone and they can hold their own.”

Watch the powerful Knockout round here: