Ruby (Steff White) was first Introduced in Series 4, Episode 6 (The Big Grapple)
Ruby at first is Dani`s energetic personal fitness trainer, who later becomes good friends with her and begins to regularly visit the house (taking Sam's place, who was written out of the show not long after Ruby's arrival). She has a younger sister called Maisy, who is very much like Dani's brother Max.