Brian McKnight got emotional while performing on stage with his youngest child last week.

Over the past few months, McKnight has faced criticism and boycotts of his performances and concerts after disowning his four oldest biological children and referring to them as "evil" and the "product of sin."

The "Back at One" singer, 55, drew more flak this week when he posted a video of him performing with his 1-year-old son Brian Kainoa Makoa Jr., whom he shares with his wife Leilani Mendoza.

In the Instagram video, McKnight flawlessly hit a high note while holding his youngest child with one arm on stage at the Hard Rock Live Orlando in Florida on Friday.

Brian McKnight
Brian McKnight speaks onstage at Celebrity Fight Night XXIV on March 10, 2018 in Phoenix, Arizona. Frazer Harrison/Getty Images

The toddler, who wore blue headphones, could be seen imitating his dad belting out the high note before clapping and hugging the singer -- much to the delight of the audience.

McKnight paused for a moment to wipe away tears and embrace his son as the crowd cheered.

"18 months old and 18 countries visited so far," McKnight wrote in the caption. "Thank you God for always protecting and blessing us keeping us safe in our own little world while taking Brian Jr. all over the world."

The R&B singer added that he was "feeling so incredibly grateful to be able to enjoy His greatest gift to the full, completely present celebrating every moment of every day as we love and nurture our family."

Despite the heartwarming father-son moment, some social media users were still not impressed by McKnight as a dad considering how he has treated his older children.

"Classic. Love your last child but not the other ones that came wayyy before," one person commented on his video.

Another Instagram user wrote, "No matter how beautiful this MAY LOOK. He told his other children to take a hike! I have a new family with new kids! Now that s**t is MESSED UP! I used to like him. But now I have no love or respect for him."

Brian McKnight and his sons, BJ McKnight and Niko McKnight
Brian McKnight and his sons, BJ McKnight and Niko McKnight of the group McKnight, perform during the "Hit Man: David Foster and Friends" concert at the Mandalay Bay Events Center May 9, 2009 in Las Vegas, Nevada. Ethan Miller/Getty Images

But most comments under his video were from those who were touched by McKnight's sweet moment with his youngest.

"That just made me choke up. He's adorable. The way he copied his dad was priceless," one user commented.

"Awwwwww this is so beautiful. There's no way to put this moment into words. The McKnights are a magnificent family. I love them," another comment read.

"Wow, no matter the other circumstances. This baby loves his daddy. That's his superhero, and this was a beautiful moment captured. I pray their family can heal," a different user wrote.

In addition to his youngest son, McKnight shares two sons with ex-wife Julie: Brian Jr. and Niko. He also welcomed daughter Briana and son Clyde with two other women.

McKnight has been estranged from his four oldest biological children for years and now refers to Brian Kainoa and his wife Leilani's kids from a previous relationship as his only children.

Brian McKnight and wife
Emma McIntyre/Getty Images for Celebrity Fight Night
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