Frank C. Brown Collection of North Carolina Folklore, vol. 3, no. 255, "Kitty Kline."
First reported by Louise Rand Bascom, JAFL, vol. 22 (1909), pp. 240-241. These are reproduced in Brown.
Reference to 'little bird' in some versions only; occurs in Mrs. Bascom's second text:

KITTY KLINE

Take me home to my Mommer, Kitty Kline
Take me home to my Mommer, Kitty Kline,
When the stars shine bright, and the moon gives light,
Take me home to my Mommer, Kitty Kline.
2
Take me home to my Mommer, Kitty Kline,
Take Me home to my Mommer, Kitty Kline,
With my head upon your breast, like a birdie in its nest,
Take me home to my Mommer, Kitty Kline.
3
I'm as free a little bird as I can be,
I'm as free a little bird as I can be,
I've built my nest on sweet Kitty's breast,
Whar the bad boys can't tear it down.

Take me home to my Mommer, etc.

and so on, eight verses.

"Of this song, Louise Rand Bascom remarked that it is "the ballad which is most universally known" in western North Carolina, that it "might be called the national song of the highlanders." She also noted that there are as many versions as singers.
Henry M. Belden or one of the other editors of the Brown volume on "Folk Songs of North Carolina" notes that the song is "an outstanding example of that type of folk lyric which picks up motives, recombines them, drops them, takes up others, until it is hardly possible to say whether a given text is to be reckoned a form of a particular song or not."

Several tune versions are given in Brown, vol. 5, "The Music of the Folk Songs," ed. J. P. Schinhan.
Some of the tunes (scores given) are reminiscent of "Lass of Rock Royal," another of "Old Kentucky Home," and another of "If I Had the Wings of an Angel."

Obviously a large complex.

I haven't checked previous threads for lyrics, but the principal ones in Bascomb 1909 and Brown 1962 (early versions from other singers are given there) are worth posting.