Or just the fact that he had a girlfriend and suddenly this new girl appears.liu just said that she met tyler's parents and they did not like her, not sure if that is known here or not but it's not that suprising. He probably told them she's a pedo before they even met. wouldn't surprise me.
A fair few parents have a unique way of knowing who are good and bad for their kids a lot of the time. Responsible parents, that is. They tend to be quite protective.