All that can presently (July 2023) be gleaned about The Wilton Sisters, Mae and Rosie, from sheet music covers and by Internet searching is that they were presumably American vaudeville performers who have been featured on 5 works published between 1924 and 1927.
Quoting from the Fort Wayne Journal-Gazette, Fort Wayne, Indiana, 24 February 1918, p.22a/b which described their appearance at the Palace Theatre, Fort Wayne in February 1918:
The Wilton Sisters, a couple of winning little lassies, one a comedienne of genuine talent and the other a perfect foil for her younger sister, will entertain the folks with some diversified bits of everything. The girls play the violin and piano, dance distractingly and sing delightfully, while they are unusually good to look at and pleasing in their personalities.
Their portrait on the left is taken from I'm Looking Over a Four Leaf Clover (1927) music by Harry Woods, words by Mort Dixon and published by Jerome H. Remick & Co., New York & Detroit, USA.
Surfers are welcome to contribute any further information about this performer.