In keeping with the seeming tradition of the 60s, that dolls must do something, this little doll would let out a "burp" when she was patted on her back.  She came in two sizes, a 16" and a 14" version called Tiny Baby Pattaburp.  I don't think this outfit is original to her.  The tag has been cut out, but the back closes with velcro-type fastener, which wasn't used in the mid-sixties, when this doll was marketed. 

In my recent travels I have run across this Tiny Pattaburp.  She is the smaller 14" version, and she is wearing her original pink "chiffony" dress.  These two dolls are made practically identical, other than their sizes.  The larger doll above should also be wearing a similar dress.