I think it was recently - possibly here on Gransnet - that someone directed us to a Youtube video showing how actresses who were pregnant, but were not playing someone pregnant, were filmed to camouflage their "bump". One of these tricks may be cuddling a cushion (also holding a large handbag and being filmed from the side, just showing their top half, or even just showing them from behind.)
My sister always giggles when our mother comes to visit and she sits perched on an armchair, primly holding her handbag on her lap in front of her (sometimes even dozing off).