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Joss Stone has taken part in a vigil at the Cenotaph to mark the start of this year's Poppy Appeal.
The soul singer was among the first to take part in the vigil on Thursday 23 October 2014 alongside former Royal Marine Commando Pete Dunning, who lost both legs when he was struck by a bomb in Afghanistan.
The watch was inspired by images of the repatriation of the Unknown Soldier in 1920, when guards kept a vigil at the coffin as a mark of respect.
Speaking at the start of her shift at the Cenotaph, Stone, 27, said: "There isn't one war that is more horrific than another. These men are incredibly brave and a lot of them have laid down their lives so that we can live in a peaceful environment.
"It's important for younger people to realise this because we haven't seen it (war).
"I'm a couple years off of 30 and I've never seen war. Hopefully, my children will never see war in our homes.
"The important thing - is it to remember or is it to be educated by it?"
The Super Duper Love singer was one of several supporters, including military personnel, to take turns on shift in the sunrise-to-sunset event. It comes in the centenary year of the outbreak of the First World War.
The soul star has teamed up with guitarist Jeff Beck to record this year's official charity single, No Man's Land (Green Fields of France).
Stone, who was clutching a photo of her great-great-grandfather Private Alfred Ernest Stenning during her solemn stint at the memorial, said: "After singing the song No Man's Land, everything that I thought got bigger and bigger.
"The lyrics in it, the song speaks of 'do you have a wife, or a sweetheart?' That really got me. It brings it closer to home."
It is estimated that around 45 million poppies will be distributed by the Royal British Legion (RBL) and its supporters as part of this year's campaign.
Mr Dunning, 29, from Wallasey in Merseyside, said: "I'm honoured to be a part of this historic event. The RBL is the nation's custodian of remembrance and this is a great way for anyone, whether they have served or not, to remember a loved one and celebrate our armed forces.
"The support that the Legion has offered me since my accident has been great. They are helping me to live my life as best I can by making my day-to-day living easier."
Teenage cadet Kamil Cesarz, 18, from Ealing, west London, who stood at another corner of the memorial with Mr Dunning and pop star Stone, said: "Being asked to take part in the watch is especially important to me. To be asked to represent 'the future' of the armed forces makes me extremely proud."
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