Leaving her ex, Toadie (played by Ryan Moloney), a mysterious letter giving him full custody of their daughter and her possessions, fears for Sonya's (Eve Moray) wellbeing are growing.
The back of the note is what troubled Toadie the most, as he discovered it said that everyone would be better off without Sonya.
It seems there's little that can be done by the police force, as Mark Brennan (Scott McGregor) struggles to help his friend look for Sonya because she isn't a missing person yet.
With their daughter Nell wondering where her mother is, will Toadie be able to track down Sonya before it's too late?
Toadie is horrified to read Sonya's letter, but will she be okay? Neighbours kids then & now Fri, January 20, 2017
Neighbours stars then and now. Take a look at what kids from Erinsborough High did next.
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Libby Kennedy – Kym Valentine left Ramsay Street in 2008 and recently gave birth to her second child
Elsewhere, the story is heating up between Finn Kelly (Rob Mills) and Susan Kennedy (Jackie Woodburne) as the former is deep in his plans for taking over Erinsborough High.
Eager to make a mark in his role as acting principle, evil Finn has already fired his ex Elly Conway (Jodi Anasta) in a desperate attempt to stop her from meddling.
With him only just getting started, what else will the scheming teacher do to regain power?
The battle for principle is hotting up, but will Finn or Susan come out on top?
According to long-serving star Jackie, viewers haven't seen the worst of Finn yet.
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She exclusively told Express.co.uk: "That's not the worst. He comes in as acting principle and causes a lot of damage to the school.
"He does a lot of things that put people at risk several times. He feels justified in taking risks with other people," Jackie teased.
Neighbours airs weekdays on Channel 5 at 1:45pm.