Debbie (Charley Webb) will soon tell Andy that they should try to conceive a child the natural way as part of their ongoing saviour sibling storyline.
The pair have already pursued other ways of having a child together for Sarah's sake, but the latest plan will prove to be the most shocking yet for their respective partners Alicia Gallagher (Natalie Anderson) and Cameron Murray (Dominic Power).
Fletcher told Soaplife of Debbie's suggestion: "Andy thinks it's a wind up. When he realises it's not, he's extremely shocked she's even mentioning such a thing. Apart from anything else, Andy can't see how Cameron and Alicia would accept it.
"He's very concerned about telling Alicia. He nearly lost her over the whole artificial insemination baby thing, so he's bound to lose her over this."
Confirming that a stunned Alicia soon decides to leave Andy, the actor continued: "He's hurt, but at the same time he knows he must do all he can to help Sarah. He's definitely willing to sacrifice his relationship for his daughter. He'll do whatever it takes, and if that means him losing everything around him, he's prepared for that to happen."
Fletcher added that Andy does not consider the possibility he could develop feelings for Debbie as a result of the plan.
"He's not anticipating that he will. He's a man - he can do sex without emotions," he explained. "But then things like that happen without you expecting them."
Emmerdale launched the saviour sibling storyline in October.
> Emmerdale's Cameron, Debbie should stay together, says Dominic Power
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