This is a cute vintage Hawaiian shirt from the 1950s to early 1960s, sized for a young child. Labeled "Ui Maikai", made in Hawaii”, it's a red cotton tropical map print of airplanes, island names, compass & flower leis. The buttons are gold-tone metal with horizontal buttonholes on the classic style short sleeved Aloha shirt with moderately pointed collar. The chest pocket is perfectly matched. I'll bet that SOMEWHERE there's a Dad's version of this pint-size wonder! 
 
Pre-owned, used; in terrific condition with no noted flaws. 
 
Size isn't marked on the label. I'd guess it's approx. a modern size 3-4 but please read the actual shirt measurements I've added below--
 
Chest pit to pit- 13 1/2" 
Front shoulder to hem length- 14 1/2"