Tracy suffers heartache when she miscarries the twins, but then sets out to hurt her nemesis.
A hurt and anxious Tracy keeps the tragic news from Steve at first, but then makes her revelation after an argument with Becky.
She goes a step further by telling Steve a big fat lie about how the miscarriage occurred, leaving Becky shocked by the allegation and her relationship with with Steve in tatters.
Kate Ford, who plays Tracy, said: "Anyone who feels sorry for Tracy won't feel sorry for long. She's going to do something pretty horrendous."
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