The pitter-patter of tiny feet

Does anyone know where this phrase (the pitter patter of little feet) comes from? Is it part of a quotation or longer phrase?

Thanks!
Gambrill
Houston, TX

Henry Wadsworth Longfellow, "The Children's Hour"

Between the dark and the daylight,
When the night is beginning to lower,
Comes a pause in the day's occupations,
That is known as the Children's Hour.

I hear in the chamber above me
The patter of little feet,
The sound of a door that is opened,
And voices soft and sweet.

www.americanpoems.com/ poets/longfellow/thechildren.shtml

Thank you. The phrase now often heard is along the lines of "Soon there'll be the pitter-patter of tiny feet", meaning that a couple will soon start a family.