Villanelle's pop-art pyjama was specifically made for the show. Costume designer Charlotte Mitchell deliberately tailored it to make it too small for Jodie Comer to fit.
Both Eve and Villanelle deal with their stress by eating candy.
Villanelle eventually does take a "Superbe!" sticker from the children's table in the French hospital, and it's visible briefly on her gown in later close-ups.
Sandra Oh has a moment in the bath when she is sat there in shock and Niko comes in. The scene is similar to one in Greys Anatomy: Remember The Time when Sandra Oh's character Cristina Yang is sat in a bath in shock and her husband Owen Hunt is talking to her.