I recently watched the (1997) Hamish Macbeth episode "The Good Thief" where there is a singing competition between local kids in the highlands of Scotland.

I would love to know what is the main song played at the end -- at 44:08 -- https://youtu.be/6GM6tsKhPhk?t=2648

I imagine that it is an old Scottish Gaelic song that's sung by the boy and recomposed for the credits.

Can anyone help identify?

Thanks much!
-S