Using "kamaʻāina" (friend)
* Kamaʻāina liʻiliʻi (literally "small friend")
* Kamaʻāina ʻōpio (young friend)
* Kamaʻāina keiki (child friend)
Using "pua" (flower, used as a term of endearment)
* Pua aloha (loving friend)
* Pua ʻōpio (young flower/friend)
Other options:
* ʻOlana liʻiliʻi (literally "little one")
* Keiki aloha (loving child)
The best phrase to use will depend on the context and the age of the person you are referring to.