Emilia is the long-lost aunt of established character Natasha Williams (Valentina Novakovic), and she is about to be introduced on Australian screens as part of a storyline which sees Tash attempt to find out more about her late mother.
As Natasha's father Michael (Sandy Winton) has been trying to stop her from finding out the truth about her mum, the schoolgirl hopes that Emilia could give her the answers she is looking for.
However, Stafford told TV Week that Emilia also has reasons to keep the truth from Tash.
"Emilia knew Michael at the time when Tash's mother died, and there's history there that makes it difficult for them to get along," Stafford explained.
"If they dredge up those memories, it'd open a huge can of worms - something they're both reluctant to do. There's an understanding that certain things should be kept until a later date - if not forever."
Stafford added that, despite the secrecy, Emilia is happy when Tash tracks her down.
"When Tash comes into Emilia's life she fills a huge hole," the actress said.
Stafford is sticking with Neighbours for a six-month guest stint.
> Natasha's aunt joins Neighbours: First picture, full details
> Neighbours actor promises "monumental" reveal
> Neighbours' Valentina Novakovic teases Natasha shocks
> Read more Neighbours spoilers and news
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