A "diaper cake" is a decorative item made by arranging diapers in the shape of a cake. It is often given as a gift for baby showers or new parents. It looks like a real cake but is made entirely of diapers. Full definition
Be ready to demonstrate how to use the cloth diapers - bring a few extra so you don't have to break down the cloth diaper cake for your demonstration. (realdiapers.org)