http://carnatic-composer.com/index.php?k=0a335dc7d942de51861da618f0baa6a4

Here is the original English song:

Little Boy Blue

Little boy blue, come blow your horn
The sheep’s in the meadow, the cow’s in the corn
Where is the boy that looks after the sheep?
He’s under the haystack fast asleep
Will you wake him? No not I
For if I do, he’s sure to cry!

A free translation to tamil

நீலகண்ணா தேன்குழலை ஊது

நீலகண்ணா தேன்குழலை ஊது
சோலை பூங்காற்றில் வெண்பசுவைக்கூட்டு
பால கோபாலகன் எங்கே உள்ளான்?
ஆல மரத்தடியிலுரங்கச்சென்றான்
எழுப்பிடுவாயோ  நீ செல்லக்கிளியை? அல்ல
அழுதிடும் கருநீர்விழி அழகில்லையோ?

Smt. Bhagyalakshmi Rajagopal has kindly consented to lend her melodious voice to sing this song, by setting it to (I believe) Mand, Adi.  You can listen to it here:

   http://carnatic-composer.com/samples/Neelakanna.mp3 

 Meaning, line by line, both literal and actual:

நீலகண்ணா தேன்குழலை ஊது:

Pronunciation: Neela KaNNa thEn kuzhalai oodhu

Literally (1): O blue Krishna, play your honey-flute
Literally (2): Blue eyed person (boy), play your honey-flute
Actually (2): O blue Krishna, play your flute to make music that is as sweet as honey

சோலை பூங்காற்றில் வெண்பசுவைக்கூட்டு:

Pronunciation: Solai poongaatril venpasuvaikkootu

Literally (1): In the breeze of the Shola flowers, herd the white cows
Actually (1): In the breeze that has wafted over the flowers in the Solai (meadow), herd the white cows.

பால கோபாலகன் எங்கே உள்ளான்?:

Pronunciation: Bala Gopalakan engE uLLaan?

Literally (1): Where is the boy-cowherd?
Actually (1): Where is the young (boy) protector of cows?

ஆல மரத்தடியிலுரங்கச்சென்றான்:

Pronunciation: Aala marath thadiyil urangach chendrAn

Literally (1): Under the Banyan tree, he went to sleep.
Actually (1): He went to sleep under the Banyan tree

எழுப்பிடுவாயோ நீ செல்லக்கிளியை? அல்ல:

Pronunciation: EzhuppiduvAyo nee chellak kiLiyai?  alla

Literally (1): Wake (him) up will you, the pet parrot?  Or
Actually (1): Will you wake up our dear child? Or

அழுதிடும் கருநீர்விழி அழகில்லையோ?

Pronunciation: Azhudhidum karu neer vizhi azhagillaiyo?

Literally (1): Crying black-water-eyes are not beautiful?
Actually (1): Do you think that it is not a pretty sight to look at tearful black-watery eyes? (It is common to apply Kajal (Mye), or mascara, to the eye-lashes of young children in South India. When they cry, the mascara dissolves in the tears and causes black tears to stream down their face).
Actually (2): Do you think that it is not a pretty sight to look at tears from watery black eyes?