Sharing a bed may also reduce cytokines, involved in inflammation, and boost oxytocin, the so-called love hormone that is known to ease anxiety and is produced in the same part of the brain responsible for the sleep-wake cycle.

WSJ: Who Sleeps Better at Night?

The murder was the result of months of secret meetings and phone calls between Mr Nowak and Ms Lagwinowicz, with Miss Wells-Burr oblivious to her part in the so-called "love triangle", the court was told.

BBC: Catherine Wells-Burr