The actress's volatile character Rachel Breckle is aunt to youngsters Amelia and Sean, while the children's mother Ali Spencer is also due to arrive on screens in the autumn.
Speaking of upcoming plans for Rachel and her relatives, Oaten told OK Extra: "Rachel comes across as very hard, assertive, mouthy and with a no-nonsense attitude. But then you start to see a heart of gold beneath it all. She's the sort of person who says things a lot of people think but wouldn't have the guts to say to someone."
She continued: "I don't know too much about what's going to happen. I can't wait to see what she gets up to. I do know she's looking after her niece and nephew for her sister, who's going through a difficult time, and they cause a lot of trouble.
"Her nephew latches on to Aaron, which is difficult for him after what happened with Jackson. So there's going to be all sorts of trouble."
Amelia is played by 7-year-old Daisy Campbell and Sean will be portrayed by 14-year-old Luke Roskell, while former Shameless star Kelli Hollis has signed up to play Ali.
Additionally, ex-Bad Girls actress Alicya Eyo has landed the role of Ruby Haswell, who is Ali's girlfriend.
Read more about Rachel and the other new Emmerdale arrivals:-
> Emmerdale casts feisty newcomer Rachel
> Emmerdale star promises "great" plans for newcomer Rachel
> Emmerdale's Gemma Oaten reveals anorexia battle
> Emmerdale announces new characters Ali and Ruby