Brian McKnight Calls Son With Stage 4 Cancer A 'Product Of Sin'; Admits He Stopped Helping Sick Child

Brian McKnight claims he was forced by his ex-wife to stop helping his estranged son Niko with his cancer battle.

Just days after describing his estranged biological kids Brian Jr., Niko, Briana, and Clyde as the "product of sin," the "Back At One" singer responded to a comment from a fan who suggested that he write a song about Niko, who is "dying in the hospital with Stage 4 cancer" but allegedly hasn't heard from his dad.

In a video on Instagram, McKnight -- who had just wrapped up concerts in London with Boyz II Men -- explained that he hesitated to talk about his son's cancer battle because it was a "sensitive" subject matter but decided to address it because of the many questions he has been getting.

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McKnight said he and his wife, Leilani Mendoza, immediately reached out to Niko and his wife after learning about his son's cancer diagnosis six months ago.

Niko's wife allegedly told them that she was "all alone and handling everything all by herself" at the time.

The "One Last Cry" crooner said Niko and his wife did not have health insurance and access to the proper doctors, so despite the "nonsense" that had been "going on for years," they "jumped into action."

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The 54-year-old singer explained that he and Mendoza asked for Niko's medical reports and "hand-delivered them to the best specialist in the country" who outlined a plan that would give his son the "best fighting chance."

According to the Grammy nominee, they found a treatment facility for Niko near their home and paid a deposit to secure his spot there.

But McKnight claimed that while he was arranging for Niko and his wife to fly to his home, he received a "hostile" phone call from his ex-wife and Niko's mom, Julie.

McKnight alleged that Julie ordered him to stop helping their son, saying, "Do not contact him. He does not need your help."

The singer suggested that Julie may have made the demand because him helping their son would "go against" the "narrative" that he's a deadbeat dad to their kids.

"So what are we doing? We're adhering to her wishes because that's what she wanted, and we're staying out of it," McKnight said, concluding his video by saying that he and Mendoza are "praying" for Niko.

McKnight's response garnered mixed reactions on social media. Some expressed support for him and sent their prayers to Niko.

"OMG!! Praying for Niko. I'm so sorry. Had no clue he is sick," one Instagram user wrote in the comments section of the singer's video.

Another comment read, "I'm so sorry you're having to deal with this."

"I commend you! Like the old people used to say, you can lead a fish to water, but you can't make them drink! You tried and it was turned down. What I have always learned, prayer can reach places where people can't! Praying for your son and family!" a third user commented.

But others appeared to have doubts over the singer's claims.

"Isn't Niko a grown man with a wife, but you want us to believe because his mommy said no, you stopped taking care of him?" one critic wrote.

Another commented, "I'm sorry but if he and [his] wife had agreed to come ... what [does] his mother calling you got to do with anything???"

A third comment read, "You gotta love your kids more than you hate the other parent."

Earlier this month, McKnight, who shares a young son with Mendoza, told fans during another Instagram Q&A session that he doesn't claim his four oldest biological children because they are the "product of sin."

"In order to live a life that you love, you have to get rid of the evil and the negativity - even if that evil and negativity is related [to you]," he said in a video posted on April 14.

Niko later fired back against McKnight's comments.

Writing on the Shaderoom, Niko accused his estranged dad of being the "evil" one and alleged that McKnight made him "clean his used condoms" and forged his children's signatures, according to screenshots obtained by Page Six.

On X, formerly Twitter, Niko admitted that he and his siblings were "bad children" in the past but wrote that his sisters "don't deserve this outright disrespect."

"But after all of this, I still love him so much because I know there's my dad in there somewhere. But he's a drone now. So f-king sad. Miss you, Dad," Niko tweeted.

Julie also spoke out against her ex in a video posted on Instagram, describing him as "a kid who throws a tantrum."