A sofa upholstered in linen, for example, could be updated with throw pillows made from a fabric shot through with gold metallic threads. (rismedia.com)
As a general rule, an odd number of pillows makes for the most natural, inviting arrangement: three for smaller sofas, and five for larger ones. (abqhomestaging.com)
That's why there are nursing pillows made for that problem. (giantmommy.com)