Hi all. New kid on the block here, and I have a question. I have written a nonfiction work concerning parents and their relationships with their adult child or children. In the body of this work I use the abbreviation of "AC" for Adult Child and "ACs" for Adult Children. My editor feels that the use of "ACs" is awkward as it actually translates to Adult Childrens. She advises dropping the "s", as readers would mentally adjust "AC" to singular or plural depending on the context of the usage within the sentence. I would appreciate any comments on this issue.