Is Laura’s sister really on her side?

Laura’s sister Katy is playing the supportive sibling – but then again she’s hardly loyal is she?

We already know she’s been having an affair with Laura’s ex Tom, left, which was going on while they were together.

She stands by Laura, takes time off work and goes with her to the doctor and police.

But she’s also Andrew’s work colleague. What else is she hiding, and should we trust her?