IMO the only advantage of the sleeping bag is that the kids can't kick it off! Which at the same time is the problem, if the kids get too hot when sleeping.
We (me and 2 kids 10 and 12) have given up the sleeping bags and use our duvets, if it's really cold we put blankets on top. I've been sleeping very nice and warm under a duvet and a blanket at 0 Celsius.
If you put a hot water bottle under the duvet to "pre-warm" it and make the kids wear their PJs under their clothes for some time before they go to sleep, they will not be freezing.
------------- Proud owner of a 1987 Sprite Alpine 370 EK, a cheap popup tent and a beloved retro Trio frame tent from the early seventies, called Giraffen.
We don't use sleeping bags - just a duvet instead. If I wear anything, I end up taking it off in the night so I start off naked. I just can't seem to sleep properly in clothes. Hot water bottle is good to warm up the bed before bedtime.
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