I thought I'd share one my Christmas photos from 3 years ago, when my kiddo was experiencing the fun of her first festive season...... this type of shot is nice & easy to do with children that can prop themselves up, or sit on their own (before they discover they can move on their own!).
I just used a blanket as a backdrop/floor cover, lay her on the floor and tipped two containers of Christmas baubles in her direction and snapped away!
You could also lie a small pillow in front of them, cover this with the blanket and give a little extra height to help hold them up if needed. You will need to be, of course, right down on the ground ... and if memory serves me correctly, I think I was lying down for a lot of these photos.
I had a large window full of beautiful natural light behind me in this shot, to get the nice 'catchlights' in her eyes .... which you will also see in the reflection on the decorations .... so also be aware of how you look as you may find yourself in the reflection too!.
Loads of fun and a nice & easy Christmas shot.
MERRY CHRISTMAS EVERYONE ...