She is credited with having written and composed the lullaby "Rock-a-bye Baby";[2] despite the words being in print in 1765.

The words of "Rock-a-bye Baby" first appeared in print in Mother Goose's Melody (London, c. 1765), possibly published by John Newbery (1713–1767), and which was reprinted in Boston in 1785.

[3] Rock-a-bye as a phrase was first recorded in 1805 in Benjamin Tabart's Songs for the Nursery, (London, 1805).

[5] Because of "Rock-a-bye Baby", she is credited in over 100 films, many made decades after her death.

[5] On stage, Canning appeared opposite William Gillette in his adaption of The Private Secretary.