Boy or girl from Kansas (Hays) (5)
I believe the answer is:
sasha
'boy' is the definition.
(I have seen 'Russian boy' mean 'sasha' so perhaps 'boy' could also mean 'sasha')
'from kansas hays' is the wordplay.
'from' says the answer is hidden in the clue.
'SASHA' is hidden in the letters of 'kansas hays'.
'or girl' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for sasha that I've seen before include "Russian boy" , "Possible Russian" , "young man from Russia" .)