This is a jolly story. In 1946 the Norwegian Broadcasting Corporation asked Alf Prøysen – poet, singer-songwriter and author of the Mrs Pepperpot stories which you may remember from childhood – to write a Christmas song for children. The result was Musevisa, or The Mouse Song, which is sung to a traditional tune and tells the story of a family of mice preparing for Christmas.
This is a recording of Prøysen himself singing it, but it’s a bit old and crackly. There’s a clearer version, featuring what sounds like a cameo from one or both of Pinky and Perky, here.
There is also an English translation of the lyrics here, but it sounds much better in Norwegian.
Altogether now: ♫ HEI-san og HOPP-san og fa-la-ra-la-ra… ♫