Most kids are happy with dressing up in a sheet for a kids ghost themed birthday party.   I get to decorate mine properly. Pieces of art.  They think of an idea and a back story and I get to create it.  I love paint.  I love painting on skin.  At a party with sheet ghosts and skeleton shirts we have contributed a bride that drowned on the way to her wedding,  a demon, and a radioactive burn victim.