This is why we have
wikipedia:
"There are many variations of this song in which the last four objects are arranged in a different order (for example — twelve lords a-leaping, eleven ladies (or dames a-) dancing, ten pipers piping, nine drummers drumming).[9] At least one version has "ten fiddlers fiddling," and another has "nine ladies waiting." Still another version alters the fourth gift to "four mockingbirds."
A version considered by many to be the authoritative, traditional version of the chant in England appears in The Oxford Dictionary of Nursery Rhymes,[2] as follows:
The twelfth day of Christmas, | My true love sent to me | Twelve lords a-leaping, | Eleven ladies dancing, | Ten pipers piping, | Nine drummers drumming, | Eight maids a-milking, | Seven swans a-swimming, | Six geese a-laying, | Five gold rings, | Four calling birds, | Three French hens, | Two turtle doves, and | A partridge in a pear tree."
"Some misinterpretations have crept into the English-language version over the years. The fourth day's gift is often stated as four "calling" birds but originally was four "colly" birds, using another word for a blackbird."
Looks to me like colly birds was the original, but calling birds is just as acceptable these days. We can all be happy!
