The One American Idol Performance That Will Make You Cry [WATCH]

Kelly Clarkson, the Idol who started it all, was back on the Idol stage last night and delivered one of the most emotional performances ever in Idol history.

Watch an 8-month pregnant Clarkson perform her current single, Piece by Piece from Kelly's latest album. The song dealt with her childhood and her difficult relationship with her father. The performance was filled with raw emotion and made Clarkson fight back tears.  Even the judges were close to breaking down.

See Kelly's amazing performance of Piece By Piece. Warning: You may need a box of tissues by watching this video.