Could Cersei have a secret son? (Picture: Macall B. Polay/Helen Sloan/HBO)

Warning: Contains spoilers for Game Of Thrones season seven.

A new fan theory has suggested Cersei could have a secret son on Game Of Thrones, pointing to the recent return of a certain Baratheon.

The fifth episode saw a tidal wave of returns and revelations, with Cersei announcing she’s pregnant and Gendry making a hammering return after his departure in the third season.

But could these events somehow be linked? A new fan theory reckons Gendry’s return isn’t for dragonglass mining or to revive House Baratheon, but is to cause significant complications as Cersei’s secret son.

Gendry has returned (Picture: HBO)

Detailed via fansite Winter Is Coming, the theory harks back to season one episode The Kingsroad – where Cersei describes her first-born son who died shortly after birth as a ‘black-haired beauty’.

It’s also pointed out how Cersei’s first-born son supposedly looked exactly like Robert, with Gendry being told similar things over the series by both Ned Stark and Jon Snow.

But how could her son be alive if he was killed? Cersei has previously stated how she never visited the baby’s crypt and rarely ever speaks about him at all, with brother Jaime being the father of her other three children, Joffrey, Myrcella and Tommen.

The theory suggests Cersei wouldn’t want to raise one of Robert’s legitimate children having shared a volatile relationship, with Robert not being present when the baby arrived.

So Cersei and trusted servant Maester Pycelle could have possibly exchanged a living son for a dying replacement, with her living child then possibly being raised in King’s Landing in secret.

Gendry grew up in King’s Landing and acted as an apprentice to Tobho Mott, until Joffrey made it his mission to kill every single one of King Robert’s surviving bastards with the blacksmith making it out alive – could Cersei have intervened somehow to protect him?

The massive gaping hole in this theory is Maggy the Frog’s prophecy which states Cersei would have only 3 children, meaning Gendry would be breaking that rule.

However the theory’s response to the prophecy is it simply refers to the three children Cersei has acknowledged, which is a bit of a cop-out but heck we’ll run with it.

Gendry is King Robert’s son, but could he be Cersei’s too? (Picture: HBO)

It’d certainly be a pretty excellent twist, but with so many more plausible reasons for Gendry’s return, it feels like a pretty left field choice.

The latest episode of Game Of Thrones titled Death Is A Enemy leaked online recently, being the second leak of an episode since season seven started.

Game Of Thrones season seven continues on HBO Sunday, on Sky Atlantic on Mondays in the UK at 9pm. You can catch-up on Now TV.

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