Change of sleeping patterns.........

[Margaret the dwarf]

Quick question about my dwarf's sleeping patterns. For the first year my dwarf always slept curled up down into her bedding/poofy stuff. A lot of the times she would completely cover herself if not surrounded by bedding. But sometimes lately she has been just falling asleep laying right on top of her bedding and laying out flat instead of curled up. I've never seen her do this before. Any ideas of what it means? Is she hot? Or just getting old? Thanks for any help. She is currently 14-15 months old. And she started this habit about a 1-2 months ago.