Open Question: How many layers does your toddler wear at night when camping?

I'm taking my 12 month old camping in the UK this weekend for the first time.

I've got a Vango Nitestar baby sleeping bag but am unsure how many layers to dress my baby in for bedtime. It's forecast to be 7-9 degrees celsius.

Any guidance from camping parents gratefully received!

Source:
http://answers.yahoo.com/question/index?qid=20110420033936AAX3FTs

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