The comments beneath the videos often feature timestamps referring to moments when the children are in compromised positions. Other comments openly use sexually explicit language in reference to the children.
YouTube responded to the latest scandal by purging tens of millions of comments from the site.
"Any content - including comments - that endangers minors is abhorrent and we have clear policies prohibiting this on YouTube," YouTube said in an official statement.
"We took immediate action by deleting accounts and channels, reporting illegal activity to authorities and disabling comments on tens of millions of videos that include minors. There's more to be done, and we continue to work to improve and catch abuse more quickly."
As is often the case with user-generated, keeping the platform safe is, however, a never-ending battle.
The issue has sparked enough concern in the local market that the Association of New Zealand Advertisers (ANZA) has sent out a statement warning brands of the risks associated with platforms such as YouTube.
In the statement, ANZA chief executive Lindsay Mouat said: "It is clear that the volume of content uploaded to platforms makes it extremely difficult to police. Machine learning solutions and a human review facility may increase the volume of inappropriate content identified and removed, but these problems continue to surface and this remains a deep concern."
Mouat went on to say that no amount of content that endangers minors is acceptable.
In addition to Spark, several major brands such as Disney and Nestle also halted their advertising on YouTube because their ads were played alongside videos with abusive or sexually explicit comments.
This follows on from a brand boycott a couple years ago when advertisers protested the placement of their spots in inappropriate videos.
YouTube said it has been hiring more experts dedicated to child safety on the platform and identifying users who wish to harm children.
But the scandals keep coming. Just this week, paediatrician Free Hess made the news when she discovered that a YouTube video targetted at kids featured a section in which a man appeared giving instructions on how to commit suicide.
The scene, which been spliced into videos from the popular Nintendo game Splatoon on YouTube and YouTube Kids, shows the man holding what appears to be an imaginary blade to the inside of his arm and then explaining how to effectively slice the wrist.
A spokesperson from YouTube told the Washington Post that the company works to ensure that the platform is "not used to encourage dangerous behaviour and we have strict policies that prohibit videos which promote self-harm."
"Every quarter we remove millions of videos and channels that violate our policies and we remove the majority of these videos before they have any views. We are always working to improve our systems and to remove violative content more quickly."
- Additional reporting from Washington Post
