Mackenzie Boyd chose his now-wife Charity Dingle over the mother of his child Chloe Harris when she went into labour on his wedding day but Emmerdale viewers suspect another village resident could play a role in the couple's demise.
Ever since Chloe decided to keep her baby, ITV soap fans have been waiting for the Dingle stalwart to find out the truth about her lying partner.
Once Charity discovers the huge betrayal, she may find herself drawn to a former flame, according to one fan's predictions.
Writing in an Emmerdale forum, one Emmerdale fan questioned the identity of the "love of Charity's life".
They wrote: "I used to say Cain but then she seemed like Vanessa was and brought out the best in her but maybe Charity herself has calmed down a bit, but she seems to be totally over Vanessa and has even moved on and married the guy she cheated on her with so, maybe Vanessa was not that special after all.
"And makes me think why she still dislikes Moira is not about Mack but about Cain as she is the one who replaced her in Cain's affection as she probably always has and will always carry a torch for Cain even if she loves others but knows Cain totally loves Moira and he doesn't love her that anyway anymore so has to move on.
"I think the whole Mack thing is forced, I think they probably won't last much longer once Charity finds out the truth."
Meanwhile, Emmerdale boss Jane Hudson has promised fans they won't have to wait too much longer for Mack's secret to finally be exposed.
Speaking to Mirror and other media at an Emmerdale press event, Hudson commented: "We all know there's a big secret due to come out. Mack's got a baby and it's Chloe's. So the question is when is that going to come out – and it is very soon.
"The big choice for Mack is going to be: does he want to be a dad and does he want to be a husband? Can he be both, or can he not be both? How is Charity going to respond? We know she is fiery.
"And can Chloe remain in the village when this secret comes out? Because it's not going to be nice when you've got the wrath of the Dingles."
Got any theories or thoughts on the storyline? Let us know in the comments section below.
