Trys Keturiose - sutartinė "Gervela, dai čiūto" (Lithuanian folk glee) 

Labai gražu :)

Well, you're right about that in the song the crane birds _are_ about to leave and the sun _is_ indeed getting cold - as to why that is so, I don't know either... Maybe it's because that year's rye had already been reaped and people won't be needing the heat till the next Spring: the sun cools down because the people tell her to with these rye-reaping songs - if they wouldn't sing to her, the sun wouldn't know when to cool down :)

Baltic folk Perhaps it just needs to die to be re-born.

Jan Tilli Perhaps :) Lithuanians have some old folk tales featuring personified sky bodies that attempt explaining the sun's absence during the winter as an act of revenge on the fortune goddess Laima: the goddess made a wedding but didn't invite Sun to it, so the Sun got offended and didn't rise for 9 days and then didn't heat up the dew for 9 more days. There are no polar nights in Lithuania - the sun rises each day even in Winter, so, some ethnologists consider that tale an indication that in the past the ancestors of Lithuanians may have lived in more Northerly latitudes where the polar nights last ~9days each Winter. Another possibility is that Lithuanians have simply borrowed and translated this tale from their Northern neighbors. Do you know if there are similar folk tales in Finland?

Baltic folk In Kalevala after Väinämöinen and Ilmarinen have stolen Sampo, Louhi hids the Sun, Moon and Fire. Ilmarinen restores Fire and also makes Sun and Moon anew, but is unable to make them work so to say. At this point Väinämöinen and Ilmarinen travel to North where they are able to force Louhi to free Sun and Moon from the mountain cave she has hid them. So all in all not very similar to your Balt folk tale :)

Baltic folk During springs there has been a tradition of Helkajuhla in parts of Finland. In this feast young maidens form two parties which sing songs as they walk to "Helka-mountain". As they reached it these parties join together and form into a circle which represents the sun.In the middle of the circle they burn a fire. With songs the girls lure the Sunship in and burn it in the fire thus capturing the Sun and it's lifegiving force for the time of summer. This is of course a fertility rite.