Samantha Murray with her daughters (l-r) Emily, 7, Zara, 2, and Lauren, 4, will be celebrating Christmas without their father, who is serving with the Australian Army in Afghanistan.

Samantha Murray with daughters Emily, 6, left, Zara, 2, and Lauren 4, at their Gungahlin home. Photo: Jeffrey Chan

SAMANTHA Murray and her three little girls Emily, Lauren and Zara, of Gungahlin, are preparing for Christmas.

They decorated the tree last week and opened an Advent calendar.

But there is something missing, their husband and father, who is one of about 3300 Australian Defence Force personnel deployed overseas.

Mrs Murray said Christmas was providing a focus for her children and giving them something to look forward to, but they would all miss their husband and father a lot on the day itself.

''Obviously when your best friend's away it's not necessarily easy, but it's OK, we get there and deal with it how we can and it's not forever,'' she said.

Her husband, an electrical engineer, is about nine weeks into a nine-month stint in the Middle East, his third posting overseas.

Mrs Murray said they had prepared for the posting by telling their daughters' teachers and guide leaders that the girls' father was going overseas, and taking the time to teach the girls a little bit about the Middle East.

''Because [he] was missing all our birthday parties we actually had a big family birthday party where we all got to choose our favourite food and I made cake, and we got balloons and games and we just had a big party,'' she said. Emily, Lauren and Zara helped their mum put together an Advent parcel for their father, with a small gift for him to open each day before Christmas.

''I'm concerned for his safety, that's the biggest thing, especially with three little girls … but he believes and I believe in what he's doing over there so that helps as well,'' Mrs Murray said.

Defence Families Australia national convener Julie Blackburn said Christmas was an especially difficult time for those with loved ones serving overseas.

''We have such a strong focus of being with family at Christmas and in the holiday period, so as a defence family you become aware of that, particularly if your partner or a serving member is away. It could be your son or your daughter, you're aware of that, you miss them,'' she said.

Ms Blackburn said even for the families of those defence force personnel who remained in Australia, Christmas could be lonely.

The end of the year is ''peak posting period'' within the forces, she said, with many families moving across the country.

She encouraged defence families feeling at a loss this festive season to get in touch with support organisations, and urged anyone who knew someone alone this Christmas to reach out and include them in festivities.