Adult Baby Fetish
Paraphilic infranilism is dressing up as a baby or being treated as one. Also know as autonepiophilia, this fetish constitutes a major community in the world of kink. Go to any kink convention (San Francisco's Folsom Street Fair or Folsom Berlin, International Mr. Leather in Chicago - the list goes on) and you'll inevitably see a small number of people wearing adult diapers with pacifiers in their months.
In most cases, autonepiphilia is seen as a fetish role-play practice, but some people with various disorders (urinary incontinence, for example) have discovered the community as a welcoming lace for them to find partners and playmates without facing stigma or shame.