Child of the light of a darkened star
With much to carry much too far.
Under the light of a half bright moon
Calls, and sings to an unknown tune.
Dance in the shadows; laugh with the rain,
Flitter, here, gone, and back again.
In the midnight hours helping flowers grow,
Whispering secret songs daylight will never know.
My sometimes friend and sometimes not,
With no earthly beginning, end, or start,
Come quickly my friendly thief and hold my hand, my heart.
Child of the light of a darkened star,
With much to carry, much too far.
Under the light of a half dark moon,
Please, come quickly, come quietly, my friend, come soon.
I feel that some of the longer lines are forced in order to meet the rhyme pattern. It might be interesting to try and match the rhythms better, though it definitely isn't easy.
I like the piece overall though
I also think you could avoid over-use of "of" on that first line. Otherwise I like
Your work is wicked spiffy by the way <3