  YouTube is a popular video platform for sharing creative content and ideas,
targeting different demographics. Adults, older children, and young children
are all avid viewers of YouTube videos. Meanwhile, countless young-kid-oriented
channels have produced numerous instructional and age appropriate videos for
young children. However, inappropriate content for young children, such as
violent or sexually suggestive content, still exists. And children lack the
ability to decide whether a video is appropriate for them or not, which then
causes a huge risk to children's mental health. Prior works have focused on
identifying YouTube videos that are inappropriate for children. However, these
works ignore that not only the actual video content influences children, but
also the advertisements that are shown with those videos.
  In this paper, we quantify the influence of inappropriate advertisements on
YouTube videos that are appropriate for young children to watch. We analyze the
advertising patterns of 24.6 K diverse YouTube videos appropriate for young
children. We find that 9.9% of the 4.6 K unique advertisements shown on these
24.6 K videos contain inappropriate content for young children. Moreover, we
observe that 26.9% of all the 24.6 K appropriate videos include at least one ad
that is inappropriate for young children. Additionally, we publicly release our
datasets and provide recommendations about how to address this issue.
