'Little Hen' is a term of endearment used in Scotland and therefore implies a rhyme with Scottish origins.
 

'Little Hen' would often be used when referring to the daughter of the house.
 

The imagination of children, however, take the meaning of all words literally, thus any illustrations of this story always depict a little hen.
 

Little Hen Rhyme

I had a little hen, the prettiest ever seen,
She washed up the dishes and kept the house clean.
She went to the mill to fetch us some flour,
And always got home in less than an hour.
She baked me my bread, she brewed me my ale,
She sat by the fire and told a fine tale!

Little Hen Rhyme