M. Ethel Grubbs 
Last updated: 20.02.17
All that can presently (November 2015) be gleaned about by internet searching is that M. Ethel Grubbs is the one-off composer of Yum Yum (1903) published by A.W. Perry & Sons' Music Co., Sedalia, Missouri, USA.
Surfers are welcome to contribute information about this composer.