Upcoming episodes of the ITV1 soap will reveal that Megan had a baby named Robbie in her teenage years, but put him up for adoption following pressure from her loved ones.
Megan's regrets over her past come to the surface in the next few weeks, prompting half-brother Declan (Jason Merrells) to decide that he should find Robbie.
Faye told Soaplife: "She'd be furious if she knew. Megan is always telling Declan to keep his nose out of her life. They may be good at business together, but they're not good at each other's personal lives. And him interfering in this is going too far."
Revealing Megan's history, the actress continued: "She was in her late teens when she had [Robbie], but it's not revealed yet whether the baby was the result of a fling or a longer relationship.
"But it seems no-one was really there for her - neither Declan or her dad. The consensus was she should have the baby adopted and get on with her life, that she should forget it ever happened.
"She hasn't seen Robbie since she gave him up. She ignored a letter he wrote to her years back, but finding him is still something that's always at the back of her mind."
Emmerdale bosses recently announced that TV newcomer Jamie Shelton has been cast as Robbie, who arrives in the village in May.
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