TikTok: where the weird and the wonderful corners of the internet converge.
But while the short-format video sharing app has sparked many a viral trend, the latest has raised more than just eyebrows.
It's not the first quirky baby-related TikTok and it's milder than others, such as parents dancing with their baby before throwing them out of view from the camera at a certain point in the song 'Baby' by Blueface.
And who could forget the infamous challenge of spilling water on a baby or toddler's head to get a reaction, or the 'cheese slice' challenge, where parents threw slices of processed cheese onto their kids' faces.
But the latest - 'pretend to hit baby's head' challenge, is as bizarre as it is concerning to some, who have slammed parents for making their babies cry on cue for their amusement.
It involves someone holding a baby in one arm while knocking on a door as they walk past. They then act to the baby as if they hit their head on the door, soothe them and ask if they're ok, to see if they can get the baby to cry.
The trend has gone viral after user @chlorboboey posted a clip of her partner trying it out on their baby daughter.
Her video, captioned 'If you have a baby, try this', has so far clocked up more than 60 million views.
In the clip, her partner can be seen rapping on the door, before gushing over the happy baby until she begins to cry, at which point he starts laughing.
"The baby isn't faking anything. The baby is concerned about its father and shows empathy. Why do you want to make your baby cry and then laugh? Ugh," said one.
"A baby does this because they don't know how to react to things around them yet," said another.
Others were more sympathetic.
"That's kind of mean but also it's really hilarious. And way better than dumping water on the babies head."
"My child does this I'm returning that thing to get updated," joked another.
The couple have since posted another video to the social media platform, after requests to try out the challenge on the family dog.