While working as a guide dog trainer, Sonya develops a relationship with Toadfish Rebecchi, which ends when Toadie gets back together with his former girlfriend Stephanie Scully (Carla Bonner).

"[18] When Sonya is sent to check up on the progress of Toadfish Rebecchi's (Ryan Moloney) guide dog puppy, Rocky, she "soon found love" with the lawyer.

[21] However, she is unaware that Toadie is pretending to be in love with Steph to help cover up the fact she is carrying Daniel Fitzgerald's (Brett Tucker) child.

[26] Morey told the official UK Neighbours website in July 2011 that Sonya and Toadie would start to have some excitement and fun again following all the drama, but they would have to deal with a few issues first.

[16] After failing to fall pregnant, Sonya gave up hope that she and Toadie would naturally conceive a child and she went through a "mourning process", before trying to move on.

[33] The actress thought that Jade's appearance would "completely rock the boat", especially as she has the potential to cause trouble for her sister and expose her for lying to everyone.

[33] During an interview with a Channel 5 journalist, Morey revealed that the last time the siblings saw each other, they were at their grandmother Hilda's (Maureen Edwards) home and Sonya was in "a very bad place".

All of a sudden, it creates even more depth and complexity to Sonya and the decisions she's made and her motivations for things like forgiving Toadie for his and Steph's sham marriage.

"[35] Morey called the storyline "phenomenal" and noted that it would change everything that viewers thought they knew about why Sonya became part of Toadie and Callum's lives.

She told an Inside Soap columnist that they worked with the character's established backgrounds and found reasons and motivations for Sonya to act the way she did.

[41] Morey told a What's on TV writer that Naomi undermines the things Sonya does, making "small wounds into big gaping bloody cuts.

[43] Sonya's paranoia about the situation caused her to forgo her plans to take Nell trick-or-treating for Halloween and leave a GA meeting abruptly.

[54] Sonya comes to Ramsay Street to assess the progress of a guide dog puppy being trained by Toadfish Rebecchi (Ryan Moloney) and his son Callum Jones (Morgan Baker).

Steph then tells Sonya that her upcoming wedding to Toadie is a sham to cover up the fact that she is carrying Libby's estranged husband Dan's child.

After almost giving up on the idea of having a baby, Sonya takes a standard pregnancy test before donating blood, and Rhys tells her she is pregnant.

Sonya goes into labour two weeks early and due to complications, she has to be rushed to hospital, where she gives birth to Nell (Scarlett Anderson) via caesarean section.

Sonya begins an online blog about parenting and is soon contacted by Jacob Holmes (Clayton Watson), who is raising his son, Elliott (Ryder Smyth) alone.

Sonya becomes the convenor of the local Gambler's Anonymous support group and meets Patricia Pappas, her neighbour Chris's (James Mason) mother.

Toadie hires Naomi Canning as his personal assistant and her mother, Sheila (Colette Mann), warns Sonya to be wary of her daughter.

The problems in the Rebecchi marriage continue when Sonya starts spending all of her time helping Mark Brennan and Bailey Turner (Calen Mackenzie) through their issues.

Mark suspects that Patricia might be sending the letters, as Toadie is representing Josh Willis (Harley Bonner), who attacked her son.

When Sonya learns the community centre is being demolished, she asks for Tim Collins's (Ben Anderson) help as he is interim Mayor, but he double-crosses her.

Sonya also learns that she has a half-sister called Zoe Mitchell (Nicola Billie Gullotti), who has leukaemia and requires a bone marrow transplant.

She later remembers that she was the one who crashed Amy's ute into the Erinsborough Backers' injuring Piper Willis (Mavournee Hazel) and David Tanaka (Takaya Honda) and makes a confession to the police.

Doctors find a large cyst on her ovary – unrelated to Alice's poisoning – and after she has it surgically removed, Sonya is told she has stage four ovarian cancer, which has already spread to her gastrointestinal tract, liver and brain.

Sonya begins intensive chemotherapy but the situation becomes more stressful when Andrea sends lawyers to assess the Rebecchis' suitability as Hugo's guardians.

Sonya confides in Toadie's brother Shane Rebecchi (Nicholas Coghlan) that when she went to Tasmania, Andrea told her about a man who mistook her for a woman called Karen, as they look alike.

[69] In 2015, a Herald Sun reporter included Sonya being revealed as Callum's mother, plus her and Toadie's pregnancy plot in their "Neighbours' 30 most memorable moments" feature.

[71] After seeing Sonya's final episode, Laura-Jayne Tyler from Inside Soap wrote that Morey and Moloney's performances were "sublime, and deserve to win every award going.

"[72] A campaign to secure Morey a nomination for the Logie Award for Most Popular Actress began on social media shortly after the episode aired.