ant-dec-laughing

Declan Donnelly in tears as he talks about friendship with Ant McPartlin

The pair have been close friends for decades

Emmy Griffiths

The first trailer for Ant and Dec's DNA Journey has been released, and it shows the pair becoming incredibly emotional as they trace back their family history in a one-off show for ITV. In the clip, Dec opens up about his friendship with Ant and becomes very emotional, even shedding a tear as he admits how lucky they were to have found each other.

The TV presenter said: "It's not lost on us how lucky we are that we met each other. We get along so well. I'm getting emotional now!" He later admits that he has never cried so much on television as his time on the show. Speaking about the documentary, Ant said: "I'm a bit of a geek when it comes to historical events, so to get the chance to research our family history using our DNA was too good an opportunity to pass up. What we find out is mind-blowing and nothing either of us could ever have imagined. It's something that will stay with us both forever." Dec added: "A huge part of this was to find out my heritage, especially on my dad’s side. I always thought I knew a fair bit about where I came from but it turns out I was wrong! Whilst it was incredible to find out about the past, what was hugely overwhelming was to meet relatives neither of us knew we had. It was a truly amazing experience."

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The pair are as close as they ever were after a turbulent couple of years, where Ant struggled with alcohol and painkiller addiction, and underwent treatment after causing a car crash due to drink driving. In an interview with The Guardian, Dec said: "We’d got to a point where we took our relationship for granted. We just assumed it would always be there. We took our eye off the ball a bit." Ant added: "I did, especially. I mean, we lived three doors apart, we'd get in the car, go to work, and the work on screen never suffered. But you get to a point where you're with each other every day, and you don't talk as much."

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After Ant underwent treatment, the pair began to rekindle their friendship, with Ant saying: "For the first time in many years, all we talked about were deep things like how we felt and what the future held, and where we were, and all the chaos that has come along, especially for me. We are blokes in our early 40s and things change."