Crown
¯\_(ツ)_/¯
Some (but not all) kids channels were having problems with monetization mainly due to "duplicate content" - There were channels who were gaming the system by making hundreds of very similar "kinda surprise" / nursery rhyme / ABC etc videos and uploading them with slight variations on the keywords in order to try to fill up search / suggested videos with their videos. So long as you're not doing anything like that, you shouldn't have any issues.