My boyfriend calls me "little one"?

So the boy that i am currently in a relationship with always calls me "little one" over text.

Ex: "hey there little one :)"

I'm just wondering exactly if this is a term of affection that makes me a little sister to him (since i am 3 years younger) Or, if it's just a cute nickname kinda thing. Plus, it seems strange since I am 5'9". Any thoughts? Thanks!
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+1 y
okay, recently also called me "kid", as in, "hey there kid"...so weird...
My boyfriend calls me "little one"?
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