Outlander makes adorable Father's Day announcement by casting actor's real sons which leaves fans in tears

Outlander's prequel Blood of My Blood made a huge casting announcement today introducing the characters who will play young Rupert and Angus - and it's their real life sons.

Rupert, played by Grant O'Rourke and Angus played by Stephen Walters, were unfortunately killed off just after the battle of Culloden much to the fans' devastation as the comical duo had become firm favourites.

The new prequel delves into the early lives of Jamie's parents in the 18th-century Scottish Highlands and Claire Fraser's parents during World War I in England.

The spin-off aims to broaden the horizons of the beloved original series... meaning that young Angus and Rupert will be featured.

And Outlander bosses decided to cast the duo as the original actor's real life sons, Louis and Marlow.

Sharing the very sweet video, the official Outlander page wrote: "Get ready for the sweetest Father’s Day casting news ever. Young Rupert and Angus are coming to #BloodOfMyBlood, played by none other than @grantorourke and Stephen Walters’ actual sons! #Outlander."

In the clip, the old duo can be seen with their offsprings and they say: "These are our sons!"

Grant says: "I'm Grant O'Rourke and I played old Rupert." His son then says: "I'm Louis O'Rourke and I play his younger self, young Rupert!

"I'm Marlow Walters and I play the young version of Angus Mhor.

And his dad says: "I'm Stephen Walters and I played old Angus. To see our children get to play a younger version of us, we've been getting photos of everything, standing backstage taking photos of them.

Stephen added: "Even though we are no longer in it, in a way, we are!

Louis then adds: "It's great to be in Outlander!"

And fans absolutely loved the news of the new casting and flocked to the comments.

One fan penned: "Happy Father’s Day everyone. This was my favourite casting of the season."

Another said: "Seriously you guys deserve a Nobel prize for your casting authenticity. So cute and awesome that they get to play their father’s characters as kids. I’m already down for a spin off of Angus and Rupert’s adventures as kids and growing up together."

While one added: "OK, why am I actually crying about this announcement?? This is the sweetest thing ever! well done casting department."

One commented: "oh my goodness!! Without a doubt one of the most incredible things @outlander_starz has ever done!!! Well done boys!! You are already as beloved as your fathers were in this fandom."

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