I want to be an angel. Sidney P. Gill. [For Purity.] In the S. MSS. (W. 50) there is a letter from Mrs. Anna Reed Wilson, of Newark, New Jersey, to Mr. Randolph, of New York, respecting this hymn and its authorship. It is dated "Newark, N.J., Feb. 6th, /73," and in it Mrs. Reed says:—
"My sister's fall name is Miss Sidney P. Gill. (An odd name for a woman, but coming down from a Welsh ancestress.) The hymn was written in Philadelphia when my sister, then a very young lady, taught the Infant Sunday School of Dr. Joel Parker's Church, of which she was a member. She had been teaching a lesson on Angels (I believe), when a lovely little girl exclaimed ‘Oh I want to be an angel.' The child within a few days was attacked by a fatal disease and died; and under the strong impression of the circumstance, the little hymn was written, and sung in the S. School. The first knowledge we had of its being in print was finding it in a Dayton, Ohio, newspaper .... I cannot give you the exact date of its composition, but think it must have been about /54."
This hymn has become a great favourite with children. It is in use in all English-speaking countries, and has been translated into several languages. In some collections it is given as "I would be like an angel." This is especially the case in Great Britain. In the Presbyterian Psalms & Hymns for the Worship of God, Richmond, U. S. A., 1867, the opening line is again altered to “I want to be with Jesus,” but this change is not so popular as the former.
--John Julian, Dictionary of Hymnology (1907)
==================
I want to be an angel, p. 559, i. Hezekiah Butterworth gives in his work, The Story of the Hymns, N. Y., 1875, p. 151, the date April 19, 1845, as the day of the death of the child, and the child's name as Annie Louisa Farrant.
--John Julian, Dictionary of Hymnology, Appendix, Part II (1907)