Momtroversy: Should dads 'comfort nurse' their babies?

A dad's viral video has everyone talking.

The eight-second video has been viewed almost 5 million times since being posted last week.

"I was just sharing a moment of bonding between my daughter and I," he told "Good Morning America." "Babies, like we all know, do baby things. So even though I didn’t know that babies find the nipple for comfort, I did think the video was incredibly funny and I wanted to share that laugh with my followers and friends on my social media."

Though most comments were supportive, there were some detractors.

"This is child-abuse to the extreme," wrote one. "This man is a jerk off. Not cool brother not cool."

Another wrote: "I hate to say it but that's not cute at all."

Brown said he was unfazed by the criticism.

"I haven't responded to any negative comments because everybody is entitled to their own opinion, but maybe those opinions just lack the proper information and knowledge behind them," said the father from McDonough, Georgia.

Edith Bracho-Sanchez, a pediatrician and ABC News consultant, added, "I actually don't think there's anything about it that's that different from a baby comfort nursing on mom."

"Moms use comfort nursing to calm babies down and to bond with their babies all the time," she said.

Even Brown himself didn't realize dads could comfort nurse.

"It is normal and fine for a baby to find the nipple for comfort, but in all honesty I didn't know that before I posted the video," he said.

"Whether that's mom's breast or a pacifier, or, in this case, dad's chest, sucking is just comforting," Bracho-Sanchez said. "Should dads go out of their way to start doing this? That's up to every dad of course. Some dads are going to leave this up to mom and comfort with a pacifier or a bottle, and that's OK."