Kelly Clarkson closed Thursday night’s episode of "American Idol" with an emotional performance of “Piece by Piece” that brought the crowd — and Keith Urban — to tears.

After guest-judging for the two-hour episode, Clarkson took the stage in a jewel-studded black gown, accompanied by only piano. “Piece by Piece” is a song about how her husband is the dad her father never was. The singer struggled to get through the song, and as she broke down the crowd did, too.

Clarkson tried blaming her tears on pregnancy hormones, but few were buying it. Urban was especially emotional, his eyes red with tears by the time she finished. Jennifer Lopez and La’Porsha Renae (the night’s other star performer) were also seen wiping away tears. Clarkson wrote “Piece by Piece” after the birth of her first daughter, River. Her focus is on husband Brandon Blackstock’s great parenting, not necessarily negative events from her past.

“I don’t know what my father went through as a child, and I don’t know why he left and made the decisions he made, but everyone’s human,” Clarkson told Glamour in 2015. “Piece by Piece” is also the title track of her latest album.

Clarkson is indeed very pregnant, and admitted that she was ready to have her second child born as soon as possible. This time it will be a boy. No official due date has been shared, but all sources indicate that the baby will arrive any day.

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