Actually, in this case, the groom is a youngsters.

I've heard of much older men marrying young teenager girls. Personally, I've never seen it, because as soon as an Afghan girl menstruates, she starts a life-long reclusion, first in her family compound and then in her husband's. Of course, this type of marriages, old men and young girls, also exist in many parts of the world, in Asia and Africa.
Disregarding the lecherous aspect of this type of marriage for a moment, it is based on the survival of the species. In Afghanistan, for example, the maternal mortality rate is one of the highest in the world: 16% of Afghan women die while pregnant or during delivery. The infant mortality rate is the second highest in the world. The probabilty that a child will not see his/her first birthday is 17%. When Afghanistan was my stomping ground in the 1970s, one out a five kids did not make it to the age of five, and things have not changed today. The life expectancy at birth is 47 years!, the GNI per capita is about US$250. These problems are compounded by patriarchal Afghan traditions, as the country is for the most part rural and remote. Therefore, this type of marriage somehow guaranties the survival of the tribe: this is nature at work.
By no means am I defending these traditions, which, like I said before, exists in many other places, but one should understand the contexts. Things can be made to change, even in Afghanistan, not over night, but step by step. IMO, this will happen when people stop praying to their gods instead of REALLY being concerned about their fellow human beings and acting on it (Sorry for this last digression, but isn't it the truth?).
Nevertheless, Afghanistan is the most extraordinary place I have ever visited.
Keep on smiling.
Daniel
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"War is terrorism on a bigger budget."