Ant and Dec were left shocked when they discovered their great grandfathers were both in the army.
And and Dec
The presenting pair have filmed a new two-part ITV documentary 'Ant and Dec's DNA Journey' - which is set to air next month - and found out that while both their relatives enlisted, they had very different experiences.
However, whilst Ant McPartlin's great grandfather was a Somme war hero, Dec Donnelly was left astonished to uncover his great great grandfather had been court-martialed and branded a deserter.
Historian Glenn Fisher told the duo Dec's great-grandfather James had sold his gun to raise funds for his family after enlisting to fight in the Crimean war, but he was also a drunk and often unreliable.
He added: "If you can't be relied upon you're worse than useless."
A shocked Dec replied: "Not what I was expecting at all, nowhere near."
And proud Ant is fulfilled by the news of his heroic great-grandfather, and he admitted he was close to tears.
Ant said: "To fight at The Battle of the Somme and to be awarded the Military Medal for Bravery, he was a hero. It's quite emotional. I could have cried . . . you're so proud."
Meanwhile, the Geordie duo have announced a new "car fanatics" show 'Street Car Showdown' - which will see teams compete by turning old cars into racing motors - for BBC Two.
However, due to their contracts with rival channel ITV, the pair won't be appearing on the programme, which is inspired by their youth.
In a statement, the pair said: "We have been fascinated with this world since we were teenagers in the North East and experienced car modders meeting up on Roker seafront in Sunderland to show off their creations.
"We came up with the format to shine a light onto the untapped world of car fanatics and highlight their passion, talent and creativity.
"We are great admirers of the team at Studio Lambert and are thrilled to be partnering with them on this project."
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