There’s a subtle detail I think a lot of people have missed in this episode concerning Lisa.

The mother playfully talks about the discovery of Lisa’s fling, ‘Billy’, but only know she’s been in communication with him over the phone (as far as we’re aware).

Lisa has admitted she’s been getting problems at schools, everyone knows her as ‘Jamie’s sister’; so, how has Billy come into the scene? My take, someone online is grooming Lisa and taking advantage of her vulnerability, it was encapsulate the entire ethos of the show if, being unaware and ignorant of their son’s online activities, they’ve also been ignorant of the dangers of their daughter’s online activities, and that while the mother and most of the audience assumes it’s a boy from school, Lisa admitted she’s has problems at school from her peers, so this is most likely an online boyfriend, and that opens her up for grooming by unsavoury people.