All that can presently (August 2024) be gleaned about Baby Lester from sheet music covers and by Internet searching is that she was presumably an American child actress/singer who has been featured on just one work namely For Sale - a Baby (1903) words & music by Charles K. Harris, and published by Chas. K. Harris, New York, USA
Her portrait on the left is taken from that same work.
Surfers are welcome to contribute any further information about this performer.
Personal remarks:
Even after 121 years its composition, this song is the ultimate tear-jerker for this ancient mariner.