Bethany didn't act out as much as ringleader Tyler and sidekick Tia (who also didn't act out as much as him). During the day Bethany did get frustrated with her siblings and sometimes can get physical with them, but mostly well behaved. She is, in addition, very stubborn at nighttime when she refuses to go to sleep, making her parents' attempts at the Stay in Bed technique very challenging. Part of that was because her dad kept pulling her aggressively in her perspective.
She was 7 on Supernanny and is now 19 in 2018.
Bethany on Facebook - She appears to now have a son, which suggests she might be a Teenage Mother (and that Natalie and Martin are now grandparents).