Quoting FroggysMommy:" Kids like that arent demons because they just want to be... its because of the parents they have. So ... [snip!] ... SO is letting his kids go wild and call you fatass and smurf... then yes, he IS a piece of smurf for not being a good parent."
Not really. Some kids are just smurfs and it has nothing to do with their parents. Depending on their ages, it can have a lot to do with the kids they go to school with.
In this case, it seems like a lack of parenting. Lack of parenting isn't always the issue.