Christopher and Kimberley Hirst are serving with the army in the province of Musa Qaleh.

Lance Corporal Kimberley, 20, is with the Royal Army Medical Corps, working to treat casualties injured on patrol.

Trooper Christopher, 23, is stationed nearby with the Reece Troop, a versatile group who act as the eyes and ears of the British Army Battle Group, providing information on enemy troops.

As well as engaging in battle, the pair are also involved in a bit of sibling rivalry – with Kimberley getting promoted before her older brother.

But it's a comfort to both of them to have a family member by their side.

"We have always got on well and being together here is great – if not a little hard on mum and dad," Christopher said.

"It is Kimberley's 21st birthday this month and it will be good to be able to share that with her.

"Being on operations is very busy, so having the odd occasion like that and reminding ourselves we have normal lives too is all the more special."

Despite working close by each other, the pair have very different roles. Kimberley deals with day-to-day ailments that soldiers and civilians suffer, from minor illnesses to battle injuries.

Trooper Hirst, meanwhile, provides intelligence and fire support.

Describing her task, which also includes dealing with horrific injuries to Afghan children, Kimberley said: "While our primary role is to treat ISAF (International Security Assistance Force) and ANSF (Afghan National Security Forces) troops we also have a responsibility to treat local nationals. Sadly, these are often children. Being able to help them is so rewarding."

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