Justin Bieber made a family cry happy tears!

The 21-year-old singer went to a church in Lynwood, California and visited a rapper, Nikea, and his son, Noah, who has Down Syndrome.

Before surprising the family, Bieber said he wanted to give the father some love and "hopefully be able to bless him."

During Bieber's unexpected visit, Noah got on stage and gave an amazing rap performance as Bieber cheered him on clapping along. Cue all the tears!

"For me, being able to just witness that, it almost brought tears to my eyes," Bieber said in the clip.

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On Tuesday, he tweeted out that there's "no better feeling than giving back."

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Knock, Knock Live is a life-changing series that helps grant wishes to unsuspecting people.

On the first episode, David Beckham surprised the Gonzales family and delivered seven new iPhones with a 10-year prepaid plan and $100,000!

Bieber's episode airs tonight on Fox at 9/8c.

Check out the video below to see how Bieber surprised a couple on their honeymoon.