More children are mimicking inappropriate pornography-inspired sexual behavior. Behavior that they do not fully comprehend but have not been taught to process. Sexual behaviors are being mimicked in the same way other behaviors are mimicked by children.
According to a recent article by Dawn Hawkins of the National Center on Sexual Exploitation (NCOSE), "The real blame in such cases rests on us, not on the children involved. We have allowed our society to become inundated with sexually explicit media and hardcore pornography. We have given our children unfettered access to this material via Internet-connected devices."
https://abstinence.net/2018/08/08/waiting-until-marriage-whats-the-big-deal/