I can't really recall HRH sitting like that much at all. She sits on her hind legs but her tushy isn't on the ground most of the time when she is outside waiting to be let back in.
In the house she usually lays in her bed or on the loveseat or if out on the floor she spreads out frog style. I couldn't find a frog style pic, but did find this one that I love.
This is a more normal pose for her.