If anything, it gets worse and Robby hesitates for another moment longer and then he pushes open the door that leads into Jack's bedroom. The light from the bathroom is dim, but it's enough to make out Jack twisted hopelessly in his sheets, his hands fisted in his pillowcase. He can see how much Jack is sweating, the sheen on his bare back. Academically, he knew that Jack probably had to have nightmares -- it's part and parcel of the PTSD diagnosis -- but this is the first time he's seeing it happen.

There's an alarm chiming in the dark. It takes Robby a moment to realise that it's Jack's smart watch.

"Jack?" he says, voice soft as he pads towards the bed. "Hey. Jack."